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rfc:rfc4912

Network Working Group S. Legg Request for Comments: 4912 eB2Bcom Category: Experimental July 2007

                 Abstract Syntax Notation X (ASN.X)

Status of This Memo

 This memo defines an Experimental Protocol for the Internet
 community.  It does not specify an Internet standard of any kind.
 Discussion and suggestions for improvement are requested.
 Distribution of this memo is unlimited.

Copyright Notice

 Copyright (C) The IETF Trust (2007).

Abstract

 Abstract Syntax Notation X (ASN.X) is a semantically equivalent
 Extensible Markup Language (XML) representation for Abstract Syntax
 Notation One (ASN.1) specifications.  ASN.X completely avoids the
 numerous ambiguities inherent in the ASN.1 language; therefore,
 specifications written in ASN.X are much easier to parse and manage
 than original ASN.1 specifications.  ASN.X, together with the Robust
 XML Encoding Rules (RXER), constitutes a schema language for XML
 documents that offers, through other ASN.1 encoding rules,
 alternative compact binary encodings for XML instance documents.

Legg Experimental [Page 1] RFC 4912 Abstract Syntax Notation X July 2007

Table of Contents

 1. Introduction ....................................................4
 2. Conventions .....................................................5
 3. General Considerations ..........................................6
    3.1. Annotations ................................................7
 4. ModuleDefinition Translation ....................................8
 5. Translation of Assignments .....................................11
    5.1. Referencing Named Constructs ..............................11
    5.2. Importing Namespaces ......................................12
    5.3. TypeAssignment Translation ................................14
    5.4. ValueAssignment and XMLValueAssignment Translation ........14
    5.5. ValueSetTypeAssignment Translation ........................15
    5.6. ObjectClassAssignment Translation .........................15
    5.7. ObjectAssignment Translation ..............................16
    5.8. ObjectSetAssignment Translation ...........................16
    5.9. ParameterizedAssignment Translation .......................17
 6. Translation of Types ...........................................17
    6.1. Identifier Replacement ....................................17
    6.2. DefinedType Translation ...................................18
    6.3. Translation of Built-in Types .............................20
    6.4. BitStringType Translation .................................21
    6.5. IntegerType Translation ...................................22
    6.6. EnumeratedType Translation ................................24
    6.7. PrefixedType Translation ..................................25
         6.7.1. Short Form TaggedType Translation ..................28
         6.7.2. Long Form TaggedType Translation ...................29
    6.8. SelectionType Translation .................................30
    6.9. InstanceOfType Translation ................................31
    6.10. ObjectClassFieldType Translation .........................31
    6.11. TypeFromObject and ValueSetFromObjects Translation .......32
    6.12. Translation of Combining Types ...........................32
         6.12.1. NamedType Translation .............................32
         6.12.2. SequenceType Translation ..........................36
         6.12.3. SetType Translation ...............................38
         6.12.4. ChoiceType Translation ............................39
         6.12.5. Translation of UNION Types ........................40
         6.12.6. SequenceOfType Translation ........................41
         6.12.7. Translation of LIST Types .........................42
         6.12.8. SetOfType Translation .............................42
         6.12.9. Effect of Insertion Encoding Instructions .........43
    6.13. Translation of Constrained Types .........................43
         6.13.1. Constraint Translation ............................46
         6.13.2. UserDefinedConstraint Translation .................46
         6.13.3. TableConstraint Translation .......................47
         6.13.4. ContentsConstraint Translation ....................49
         6.13.5. ExceptionSpec Translation .........................50

Legg Experimental [Page 2] RFC 4912 Abstract Syntax Notation X July 2007

 7. Translation of Values ..........................................51
    7.1. Translation of Literal Values .............................53
    7.2. Translation of Notational Values ..........................54
         7.2.1. DefinedValue Translation ...........................56
         7.2.2. BuiltinValue Translation ...........................57
         7.2.3. ValueFromObject Translation ........................60
         7.2.4. ObjectClassFieldValue Translation ..................60
 8. Translation of Value Sets ......................................61
    8.1. ElementSetSpecs Translation ...............................62
    8.2. ElementSetSpec Translation ................................62
    8.3. SubtypeElements Translation ...............................63
         8.3.1. ValueRange Translation .............................64
         8.3.2. InnerTypeConstraints Translation ...................65
 9. Translation of Object Classes ..................................66
    9.1. DefinedObjectClass Translation ............................66
    9.2. ObjectClassDefn Translation ...............................68
         9.2.1. TypeFieldSpec Translation ..........................68
         9.2.2. FixedTypeValueFieldSpec Translation ................69
         9.2.3. FixedTypeValueSetFieldSpec Translation .............70
         9.2.4. VariableTypeValueFieldSpec Translation .............71
         9.2.5. VariableTypeValueSetFieldSpec Translation ..........73
         9.2.6. FieldName Translation ..............................74
         9.2.7. ObjectFieldSpec Translation ........................75
         9.2.8. ObjectSetFieldSpec Translation .....................76
 10. Translation of Objects ........................................77
    10.1. DefinedObject Translation ................................77
    10.2. ObjectDefn Translation ...................................78
    10.3. ObjectFromObject Translation .............................80
 11. Translation of Object Sets ....................................80
    11.1. DefinedObjectSet Translation .............................81
    11.2. ObjectSetElements Translation ............................82
         11.2.1. ObjectSetFromObjects Translation ..................83
 12. Translation of Information From Objects .......................83
 13. Translation of Parameterized Definitions ......................83
 14. EncodingControlSections Translation ...........................93
 15. Security Considerations .......................................94
 16. Acknowledgements ..............................................94
 17. References ....................................................95
    17.1. Normative References .....................................95
    17.2. Informative References ...................................97
 Appendix A. ASN.1 for ASN.X .......................................95
 Appendix B. ASN.X for ASN.X ......................................115

Legg Experimental [Page 3] RFC 4912 Abstract Syntax Notation X July 2007

1. Introduction

 A full parser for the Abstract Syntax Notation One (ASN.1) language
 [X.680][X.680-1][X.681][X.682][X.683] is difficult to implement due
 to numerous ambiguities in the notation.  For example, certain
 notations for a Value are syntactically indistinguishable from
 notation for a ValueSet, Object, ObjectSet, DummyReference, or
 SimpleTableConstraint.  An ObjectClassAssignment, ObjectAssignment,
 or ObjectSetAssignment resembles respectively a TypeAssignment,
 ValueAssignment, or ValueSetTypeAssignment.  A
 FixedTypeValueFieldSpec or FixedTypeValueSetFieldSpec resembles
 respectively an ObjectFieldSpec or ObjectSetFieldSpec, and an
 ObjectClassFieldType resembles InformationFromObjects notation.  In
 general, such ambiguities can only be resolved once the entire
 specification has been parsed.  There are other notations that are
 not mutually ambiguous but still require several lexical tokens to be
 scanned before they can be distinguished from each other.  The
 difficulty of parsing ASN.1 is an impediment to its wider adoption.
 This document defines a semantically equivalent Extensible Markup
 Language (XML) [XML10][XML11] representation for ASN.1 specifications
 called Abstract Syntax Notation X (ASN.X).  An ASN.X module is a
 well-formed and valid XML document conforming to XML namespaces
 [XMLNS10][XMLNS11].  ASN.X completely avoids the inherent ambiguities
 of the ASN.1 language; therefore, specifications written in ASN.X are
 much easier to parse and manage than original ASN.1 specifications.
 For example, any conformant XML processor forms the basis of an ASN.1
 toolkit.
 ASN.X, together with the Robust XML Encoding Rules (RXER) [RXER],
 constitutes a schema language for XML documents that offers, through
 other ASN.1 encoding rules, alternative compact binary encodings for
 XML instance documents conforming to an ASN.X specification.  ASN.X
 definitions can also incorporate type, element, and attribute
 definitions from XML Schema [XSD1] documents, RELAX NG [RNG]
 documents, or Document Type Definitions (DTDs) [XML10][XML11].
 ASN.X is defined in terms of rules for translating from an ASN.1
 specification.  This does not preclude an ASN.X module being written
 directly without a pre-existing ASN.1 module; however, such an ASN.X
 module is considered valid if and only if there exists, in principle,
 an ASN.1 module that when translated would yield the ASN.X module.
 The format for ASN.X has also been designed so that the content of an
 ASN.X module conforms to the RXER encoding of an abstract value of an
 ASN.1 type, the ModuleDefinition type, presented in Appendix A.  This
 means that it is possible to decode an ASN.X module using an RXER
 decoder and then re-encode the abstract value (for storage or

Legg Experimental [Page 4] RFC 4912 Abstract Syntax Notation X July 2007

 transmission) using any of the other encoding rules for ASN.1.  Thus,
 the "X" in ASN.X can be regarded as standing for either XML or RXER,
 or more generally, for any set of ASN.1 encoding rules.
 The ASN.X translation of the ASN.1 module in Appendix A is presented
 in Appendix B.

2. Conventions

 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
 "SHOULD", "SHOULD NOT", "RECOMMENDED", and "MAY" in this document are
 to be interpreted as described in BCP 14, RFC 2119 [BCP14].  The key
 word "OPTIONAL" is exclusively used with its ASN.1 meaning.
 Throughout this document "type" shall be taken to mean an ASN.1 type,
 and "value" shall be taken to mean an ASN.1 abstract value.
 A reference to an ASN.1 production [X.680] (e.g., Type, NamedType) is
 a reference to the text in an ASN.1 specification corresponding to
 that production.
 The description of the translation of an ASN.1 module into an ASN.X
 module makes use of definitions from the XML Information Set
 (Infoset) [INFOSET].  In particular, information item property names
 follow the Infoset convention of being shown in square brackets,
 e.g., [local name].  Literal values of Infoset properties are
 enclosed in double quotes; however, the double quotes are not part of
 the property values.  In the sections that follow, "information item"
 will be abbreviated to "item", e.g., "element information item" is
 abbreviated to "element item".  Element items will be referred to by
 their [local name] in angle brackets, e.g., "the <type> element item"
 means the element item with the [local name] "type".  Attribute items
 will be referred to by their [local name], e.g., "the type attribute
 item" means the attribute item with the [local name] "type".
 This document uses the namespace prefix "asnx:" to stand for the
 namespace name "urn:ietf:params:xml:ns:asnx", though in practice any
 valid namespace prefix is permitted in ASN.X.
 Encoding instructions [X.680-1] referenced by name in this
 specification are encoding instructions for RXER [RXEREI].  The
 associated provisions do not apply to encoding instructions for other
 encoding rules that happen to have the same name.
 Code points for characters [UNICODE] are expressed using the Unicode
 convention U+n, where n is four to six hexadecimal digits, e.g., the
 space character is U+0020.

Legg Experimental [Page 5] RFC 4912 Abstract Syntax Notation X July 2007

3. General Considerations

 ASN.X is defined in terms of rules for translating an ASN.1 module
 into a synthetic Infoset.  This synthetic Infoset is then serialized
 into a well-formed and valid XML document (the ASN.X module) in the
 same manner that the synthetic Infoset for a non-canonical RXER
 encoding is serialized into an XML document (see Section 6.12 of the
 specification for RXER [RXER]).
    Aside: The serialization permits CDATA sections, character
    references, and parsed entity references.  However, note that an
    ASN.X module may be transferred as data in a protocol and that
    some protocols disallow entity references.
 Apart from the [document element] of the document item for an ASN.X
 module, the translation of some ASN.1 construct belongs to the
 [children] or [attributes] of an enclosing element item.
 Where the translation of the construct is an element item, it is
 appended to the [children] of the enclosing element item.  Elements
 MUST be appended to the [children] of the enclosing element item in
 the order described.  Translators MAY add white space character items
 (i.e., U+0020, U+0009, U+000D and U+000A) to the [children] of any
 element item (to improve the layout) except element items with the
 [local name] "literalValue", "fieldName", or "restrictBy".
    Aside: White space in the [children] of <fieldName> and
    <restrictBy> element items is explicitly covered under their
    respective descriptions.
 Where the translation of the construct is an attribute item, it is
 added to the [attributes] of the enclosing element item.  The order
 of attribute items is not significant.  Translators MAY add leading
 and trailing white space characters to the [normalized value] of any
 attribute item except an attribute item with the [local name]
 "literalValue".
    Aside: An attribute or element item with the [local name]
    "literalValue" holds an RXER Infoset translation of an abstract
    value, and white space characters may be significant in that
    abstract value.  In most cases, RXER itself permits optional
    leading and trailing white space characters in the Infoset
    translation.
 Translators MAY add comment and processing instruction (PI) items to
 the [children] of any element item except an element item with the
 [local name] "literalValue".

Legg Experimental [Page 6] RFC 4912 Abstract Syntax Notation X July 2007

    Aside: In most cases, RXER itself permits comment and PI items in
    the [children] of the element items with the [local name]
    "literalValue".
    Aside: Note that an ASN.X module may be transferred as data in a
    protocol and that some protocols disallow processing instructions.
 The [in-scope namespaces] and [namespace attributes] for
 <literalValue> and <restrictBy> element items are determined
 according to Section 6.10 of the specification for RXER [RXER].  The
 [in-scope namespaces] and [namespace attributes] for other element
 items in the translation are determined according to Section 6.2.2.1
 of the specification for RXER.
 The [namespace name] of any element item or attribute item generated
 by the translation from an ASN.1 specification has no value unless
 specified otherwise.  In those cases where the [namespace name] of an
 element item has a value, the [prefix] of the element item is
 determined according to Section 6.2.2.2 of the specification for
 RXER.  In those cases where the [namespace name] of an attribute item
 has a value, the [prefix] of the attribute item is determined
 according to Section 6.2.3.1 of the specification for RXER.
    Aside: Non-canonical RXER allows all valid namespace prefixes and
    all valid placements for their corresponding namespace declaration
    attributes.
 Whenever an element item is added to the [children] of an enclosing
 element item, the enclosing element item becomes the [parent] of the
 element item.
 Whenever an attribute item is added to the [attributes] of an element
 item, the element item becomes the [owner element] of the attribute
 item.  For each attribute item, the [specified] property is set to
 true, the [attribute type] has no value, and the value of the
 [references] property is set to unknown.

3.1. Annotations

 In a number of places, as indicated in subsequent sections, the
 translator is permitted to add an element item with the [local name]
 "annotation".  The [children] and [attributes] of the <annotation>
 element item are at the discretion of the translator.
 Typical uses of the <annotation> element item would be to hold
 comments from the ASN.1 specification that are normative in nature,
 e.g., a comment in a user-defined constraint, or to hold directives
 for an ASN.1 compiler.

Legg Experimental [Page 7] RFC 4912 Abstract Syntax Notation X July 2007

 Free text or XML comments in an <annotation> element will be
 preserved in a Canonical RXER (CRXER) encoding [RXER] (because the
 corresponding ASN.1 type for the <annotation> element item is the
 Markup type [RXER]), while XML comments outside <annotation> elements
 will not be preserved.
 Vendors using the <annotation> element items to hold ASN.1 compiler
 directives (as attributes or child elements of the <annotation>
 element) SHOULD use element or attribute names that are qualified
 with a namespace name specific to the vendor.

4. ModuleDefinition Translation

 The translation of a ModuleDefinition [X.680] (an ASN.1 module) is an
 element item with the [local name] "module" and the [namespace name]
 "urn:ietf:params:xml:ns:asnx" (i.e., an <asnx:module> element item).
 The element item is typically the [document element] of a document
 item.
 An attribute item with the [local name] "format" and
 [normalized value] "1.0" MAY be added to the [attributes] of the
 <asnx:module> element item.
 An ASN.1 module has a schema identity URI if it contains a
 SCHEMA-IDENTITY encoding instruction, in which case the schema
 identity URI is the character string specified by the AnyURIValue of
 the SCHEMA-IDENTITY encoding instruction.
 If the ASN.1 module being translated has a schema identity URI, then
 an attribute item with the [local name] "schemaIdentity" SHALL be
 added to the [attributes] of the <asnx:module> element item.  The
 [normalized value] of this attribute item is the schema identity URI
 of the module.
 If the target namespace [RXEREI] for the ASN.1 module is not absent,
 then an attribute item with the [local name] "targetNamespace" SHALL
 be added to the [attributes] of the <asnx:module> element item.  The
 [normalized value] of this attribute item is the target namespace of
 the module.
    Aside: An ASN.1 module has a target namespace if it contains a
    TARGET-NAMESPACE encoding instruction.
 If the ASN.1 module contains a TARGET-NAMESPACE encoding instruction
 that specifies a Prefix, then an attribute item with the [local name]
 "targetPrefix" SHALL be added to the [attributes] of the

Legg Experimental [Page 8] RFC 4912 Abstract Syntax Notation X July 2007

 <asnx:module> element item.  The [normalized value] of this attribute
 item is the character string specified by the NCNameValue in the
 Prefix.
 In examples in the remainder of this document, the namespace prefix
 "tns:" is used to stand for the target namespace of the module being
 translated.
 An attribute item with the [local name] "name" SHALL be added to the
 [attributes] of the <asnx:module> element item.  The
 [normalized value] of this attribute item is the modulereference in
 the ModuleIdentifier in the ModuleDefinition.
 If the DefinitiveIdentifier in the ModuleIdentifier in the
 ModuleDefinition is not empty, then an attribute item with the
 [local name] "identifier" SHALL be added to the [attributes] of the
 <asnx:module> element item.  The [normalized value] of this attribute
 item is the RXER character data translation [RXER] of the
 DefinitiveIdentifier.
 If the TagDefault in the ModuleDefinition is empty, then an attribute
 item with the [local name] "tagDefault" and [normalized value]
 "explicit" SHALL be added to the [attributes] of the <asnx:module>
 element item.
 If the TagDefault in the ModuleDefinition is not empty and the first
 keyword in the TagDefault is not "AUTOMATIC", then an attribute item
 with the [local name] "tagDefault" SHALL be added to the [attributes]
 of the <asnx:module> element item.  The [normalized value] of this
 attribute item is the first keyword in the TagDefault with all
 letters downcased, i.e., "explicit" or "implicit".
 If the TagDefault in the ModuleDefinition is not empty and the first
 keyword in the TagDefault is "AUTOMATIC", then an attribute item with
 the [local name] "tagDefault" and [normalized value] "automatic" MAY
 be added to the [attributes] of the <asnx:module> element item.
 If the ExtensionDefault in the ModuleDefinition is not empty, then an
 attribute item with the [local name] "extensibilityImplied" and
 [normalized value] "true" or "1" SHALL be added to the [attributes]
 of the <asnx:module> element item.
 If the ExtensionDefault in the ModuleDefinition is empty, then an
 attribute item with the [local name] "extensibilityImplied" and
 [normalized value] "false" or "0" MAY be added to the [attributes] of
 the <asnx:module> element item.

Legg Experimental [Page 9] RFC 4912 Abstract Syntax Notation X July 2007

 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <asnx:module> element item.
 The translation of each Assignment in the AssignmentList in the
 ModuleBody in the ModuleDefinition of the module being translated
 SHALL be appended to the [children] of the <asnx:module> element
 item.
 If the EncodingControlSections instance in the ModuleDefinition
 contains an EncodingControlSection for RXER, then the translation of
 each NamedType in a TopLevelComponent [RXEREI] nested in the
 EncodingInstructionAssignmentList SHALL be added to the [children] of
 the <asnx:module> element item.  The relative order of the top-level
 components [RXEREI] SHOULD be preserved in the translation; however,
 the translations of the top-level components MAY be interspersed with
 the translations of the assignments in the AssignmentList.
 The translation of the EncodingControlSections instance in the
 ModuleDefinition of the module being translated SHALL be appended to
 the [children] of the <asnx:module> element item.
 Example
    MyModule DEFINITIONS
    IMPLICIT TAGS
    EXTENSIBILITY IMPLIED ::=
    BEGIN
    MyType ::= INTEGER
    ENCODING-CONTROL RXER
        SCHEMA-IDENTITY  "http://example.com/id/MyModule"
        TARGET-NAMESPACE "http://example.com/ns/MyModule"
        COMPONENT myElement INTEGER
    END
    <asnx:module xmlns:asnx="urn:ietf:params:xml:ns:asnx"
                 name="MyModule"
                 schemaIdentity="http://example.com/id/MyModule"
                 targetNamespace="http://example.com/ns/MyModule"
                 tagDefault="implicit"
                 extensibilityImplied="true">
     <namedType name="MyType" type="asnx:INTEGER"/>

Legg Experimental [Page 10] RFC 4912 Abstract Syntax Notation X July 2007

     <element name="myElement" type="asnx:INTEGER"/>
    </asnx:module>

5. Translation of Assignments

5.1. Referencing Named Constructs

 An Assignment in ASN.1 associates a reference name with a Type,
 Value, ValueSet, ObjectClass, Object, or ObjectSet.  For ASN.X, an
 Assignment is also regarded as associating an expanded name
 [XMLNS10][XMLNS11] with the Type, Value, ValueSet, ObjectClass,
 Object, or ObjectSet.  ASN.X uses these expanded names, rendered as
 qualified names [XMLNS10][XMLNS11], in place of the references in an
 ASN.1 specification.
 In every case, the local name of the expanded name is the
 typereference, valuereference, objectclassreference, objectreference,
 or objectsetreference in the Assignment (i.e., the [normalized value]
 of the name attribute item in the translation of the Assignment,
 ignoring white space characters).  If the target namespace of the
 ASN.1 module in which the Assignment is defined is not absent, then
 the namespace name of the expanded name is that target namespace;
 otherwise, the namespace name of the expanded name has no value.
 When the expanded name is rendered as a qualified name, the namespace
 prefix is determined according to Section 6.7.11.1 of the
 specification for RXER [RXER].
 If an ASN.1 specification contains two or more modules where the
 target namespace is absent, then there exists the possibility that
 the expanded names defined by the ASN.X translations of those modules
 are not distinct.  The expanded names are not distinct if:
 (1) two or more type or value set assignments define the same
     typereference, or
 (2) two or more value assignments define the same valuereference, or
 (3) two or more object class assignments define the same
     objectclassreference, or
 (4) two or more object assignments define the same objectreference,
     or
 (5) two or more object set assignments define the same
     objectsetreference, or

Legg Experimental [Page 11] RFC 4912 Abstract Syntax Notation X July 2007

 (6) two or more top-level element components [RXEREI] have the same
     local name, or
 (7) two or more top-level attribute components [RXEREI] have the same
     local name.
 If the expanded names are not distinct, then an unambiguous
 translation into ASN.X does not exist unless each of the modules has
 a SCHEMA-IDENTITY encoding instruction.  Consequently, if two or more
 modules where the target namespace is absent are being translated
 into ASN.X and the reference names defined in those modules will not
 be distinct, then as a local action prior to the translation, a
 SCHEMA-IDENTITY encoding instruction MUST be added to each of the
 modules that defines one or more of the indistinct expanded names and
 that does not already have a SCHEMA-IDENTITY encoding instruction.
 The character string (a URI) specified by the AnyURIValue of each
 added SCHEMA-IDENTITY encoding instruction is freely chosen by the
 translator, subject to the condition that these character strings are
 distinct [RXEREI].
    Aside: Although this means that different translators might
    produce ASN.X modules that are syntactically different for any
    given ASN.1 module, those ASN.X modules will be semantically
    equivalent to each other and to the original ASN.1 module.
 TARGET-NAMESPACE and SCHEMA-IDENTITY encoding instructions are
 RECOMMENDED for every ASN.1 module.

5.2. Importing Namespaces

 An Assignment is referenced from an ASN.X module if its associated
 expanded name appears as a qualified name in the [normalized value]
 of an attribute item with the [local name] "type", "value", "class",
 "object", or "objectSet".  These references are categorized as direct
 references.  An Assignment or top-level component is also referenced
 from an ASN.X module if its expanded name appears as a qualified name
 in the [normalized value] of an attribute item with the [local name]
 "ref".  This reference is only categorized as direct if the ref
 attribute is not the result of the translation of a DefinedType
 subject to a TYPE-REF encoding instruction or a NamedType subject to
 an ATTRIBUTE-REF or ELEMENT-REF encoding instruction.
    Aside: In the case of an indirect reference, an attribute item
    with the [local name] "embedded" and [normalized value] "true" or
    "1" will also be present.

Legg Experimental [Page 12] RFC 4912 Abstract Syntax Notation X July 2007

 Definition (external module): An external module is any module other
 than the module being translated and the AdditionalBasicDefinitions
 module [RXER].
    Aside: The AdditionalBasicDefinitions module is always assumed to
    be imported, as are all the built-in types and object classes of
    ASN.1.
 An element item with the [local name] "import" SHALL be added to the
 [children] of the <asnx:module> element item for each external module
 containing Assignments or top-level components that are directly
 referenced from the ASN.X module.  An <import> element item MAY be
 added to the [children] of the <asnx:module> element item for any
 other external module.
 An attribute item with the [local name] "name" SHOULD be added to the
 [attributes] of the <import> element item.  The [normalized value] of
 this attribute item is the modulereference in the ModuleIdentifier in
 the ModuleDefinition of the external module.
 If the DefinitiveIdentifier in the ModuleIdentifier in the
 ModuleDefinition of the external module is not empty, then an
 attribute item with the [local name] "identifier" SHALL be added to
 the [attributes] of the <import> element item.  The
 [normalized value] of this attribute item is the RXER character data
 translation of the DefinitiveIdentifier.
 If the external module has a schema identity URI, then an attribute
 item with the [local name] "schemaIdentity" SHALL be added to the
 [attributes] of the <import> element item.  The [normalized value] of
 this attribute item is the schema identity URI of the external
 module.
 If the target namespace of the external module is not absent, then an
 attribute item with the [local name] "namespace" SHALL be added to
 the [attributes] of the <import> element item.  The
 [normalized value] of this attribute item is the target namespace of
 the external module.
 An attribute item with the [local name] "schemaLocation" MAY be added
 to the [attributes] of the <import> element item.  The
 [normalized value] of this attribute item is a URI [URI] indicating
 the physical location of the ASN.X translation of the external
 module.
 The <import> element items MUST follow an <annotation> element item
 (if present) and MUST precede any other element items in the
 [children] of the <asnx:module> element item.

Legg Experimental [Page 13] RFC 4912 Abstract Syntax Notation X July 2007

 Note that because of the way parameterized references are expanded in
 ASN.X (see Section 13), the modules in the Imports in the ModuleBody
 in the ModuleDefinition may not correspond exactly to the <import>
 element items.

5.3. TypeAssignment Translation

 The translation of a TypeAssignment is an element item with the
 [local name] "namedType".  An attribute item with the [local name]
 "name" SHALL be added to the [attributes] of the <namedType> element
 item.  The [normalized value] of this attribute item is the
 typereference on the left-hand side of the assignment.
 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <namedType> element item.  The translation of
 the Type on the right-hand side of the assignment SHALL be added to
 the [children] or [attributes] of the <namedType> element item.
 Example
    MyType ::= INTEGER
    <namedType name="MyType" type="asnx:INTEGER"/>

5.4. ValueAssignment and XMLValueAssignment Translation

 The translation of a ValueAssignment is an element item with the
 [local name] "namedValue".  An attribute item with the [local name]
 "name" SHALL be added to the [attributes] of the <namedValue> element
 item.  The [normalized value] of this attribute item is the
 valuereference on the left-hand side of the assignment.
 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <namedValue> element item.  The translation of
 the Type on the left-hand side of the assignment SHALL be added to
 the [children] or [attributes] of the <namedValue> element item.  The
 translation of the Value on the right-hand side of the assignment
 SHALL be added to the [children] or [attributes] of the <namedValue>
 element item.
 Example
    myValue INTEGER ::= 10
    <namedValue name="myValue" type="asnx:INTEGER" literalValue="10"/>

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 An XMLValueAssignment is converted into the equivalent
 ValueAssignment and then translated as a ValueAssignment.  Note that
 the ASN.X representation for a Value is unrelated to XMLTypedValue.

5.5. ValueSetTypeAssignment Translation

 The translation of a ValueSetTypeAssignment is an element item with
 the [local name] "namedValueSet".  An attribute item with the
 [local name] "name" SHALL be added to the [attributes] of the
 <namedValueSet> element item.  The [normalized value] of this
 attribute item is the typereference on the left-hand side of the
 assignment.
 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <namedValueSet> element item.  The translation
 of the Type on the left-hand side of the assignment SHALL be added to
 the [children] or [attributes] of the <namedValueSet> element item.
 The translation of the ValueSet on the right-hand side of the
 assignment SHALL be added to the [children] of the <namedValueSet>
 element item.
 Example
    MyValueSet INTEGER ::= { 10 }
    <namedValueSet name="MyValueSet" type="asnx:INTEGER">
     <valueSet>
      <literalValue>10</literalValue>
     </valueSet>
    </namedValueSet>

5.6. ObjectClassAssignment Translation

 The translation of an ObjectClassAssignment is an element item with
 the [local name] "namedClass".  An attribute item with the
 [local name] "name" SHALL be added to the [attributes] of the
 <namedClass> element item.  The [normalized value] of this attribute
 item is the objectclassreference on the left-hand side of the
 assignment.
 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <namedClass> element item.  The translation of
 the ObjectClass on the right-hand side of the assignment SHALL be
 added to the [children] or [attributes] of the <namedClass> element
 item.

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 Example
    MY-CLASS ::= TYPE-IDENTIFIER
    <namedClass name="MY-CLASS" class="asnx:TYPE-IDENTIFIER"/>

5.7. ObjectAssignment Translation

 The translation of an ObjectAssignment is an element item with the
 [local name] "namedObject".  An attribute item with the [local name]
 "name" SHALL be added to the [attributes] of the <namedObject>
 element item.  The [normalized value] of this attribute item is the
 objectreference on the left-hand side of the assignment.
 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <namedObject> element item.  The translation of
 the DefinedObjectClass on the left-hand side of the assignment SHALL
 be added to the [children] or [attributes] of the <namedObject>
 element item.  The translation of the Object on the right-hand side
 of the assignment SHALL be added to the [children] or [attributes] of
 the <namedObject> element item.
 Example
    myObject TYPE-IDENTIFIER ::=
        { NULL IDENTIFIED BY { 1 3 14 3 2 26 } }
    <namedObject name="myObject" class="asnx:TYPE-IDENTIFIER">
     <object>
      <field name="id" literalValue="1.3.14.3.2.26"/>
      <field name="Type" type="asnx:NULL"/>
     </object>
    </namedObject>

5.8. ObjectSetAssignment Translation

 The translation of an ObjectSetAssignment is an element item with the
 [local name] "namedObjectSet".  An attribute item with the
 [local name] "name" SHALL be added to the [attributes] of the
 <namedObjectSet> element item.  The [normalized value] of this
 attribute item is the objectsetreference on the left-hand side of the
 assignment.
 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <namedObjectSet> element item.  The translation
 of the DefinedObjectClass on the left-hand side of the assignment
 SHALL be added to the [children] or [attributes] of the
 <namedObjectSet> element item.  The translation of the ObjectSet on

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 the right-hand side of the assignment SHALL be added to the
 [children] or [attributes] of the <namedObjectSet> element item.
 Example
    MyObjectSet TYPE-IDENTIFIER ::= { myObject }
    <namedObjectSet name="MyObjectSet" class="asnx:TYPE-IDENTIFIER">
     <objectSet>
      <object ref="tns:myObject"/>
     </objectSet>
    </namedObjectSet>

5.9. ParameterizedAssignment Translation

 The translation of an ASN.1 specification into ASN.X replaces any
 reference to a parameterized definition [X.683] with the definition
 expanded in-line.  Consequently, there is no direct translation for a
 ParameterizedAssignment, though its definition may come into play in
 the translation of references to the parameterized definition (see
 Section 13).

6. Translation of Types

 The rules for translating the different varieties of Type are
 detailed in this section.
 Note that the notation of ASN.1 is ambiguous where a Type is both
 prefixed [X.680-1] (e.g., tagged) and constrained.  For example, the
 notation "[0] INTEGER (0..10)" could be interpreted as either a
 tagged ConstrainedType or a constrained TaggedType.  For the purposes
 of the translation into ASN.X, the constraint is assumed to have
 higher precedence than the prefix, so the above notation would be
 taken to be a tagged ConstrainedType.

6.1. Identifier Replacement

 Various RXER encoding instructions can be used to override an
 identifier in an ASN.1 specification with an NCName [XMLNS10].  The
 NCName is given preeminence in the ASN.X representation, and the
 identifier is not explicitly given if it is algorithmically related
 to the NCName.  The cases where an NCName overrides an identifier are
 covered individually in other parts of this specification and make
 use of the following definition.
 Definition (reduction): The reduction of an NCName is the string of
 characters resulting from the following operations performed in order
 on the NCName:

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 (1) replace each full stop ('.', U+002E) and low line ('_', U+005F)
     character with a hyphen character ('-', U+002D),
 (2) remove every character except Latin letters (U+0041-U+005A,
     U+0061-U+007A), decimal digits (U+0030-U+0039), and hyphens
     (U+002D),
 (3) remove leading and trailing hyphen characters,
 (4) replace sequences of two or more hyphen characters with a single
     hyphen, and
 (5) convert the first character to lowercase if it is an uppercase
     letter.
    Aside: If the reduction of an NCName is not the same as the
    identifier that the NCName replaces, then the identifier will be
    explicitly given in the translation into ASN.X.

6.2. DefinedType Translation

 If a Type is a DefinedType in a ReferencedType, then the translation
 of the Type is the translation of the DefinedType.
 If a DefinedType is not a ParameterizedType,
 ParameterizedValueSetType, or DummyReference and is not subject to a
 TYPE-REF or REF-AS-TYPE encoding instruction, then the translation of
 the DefinedType is either the attribute form translation of a type
 reference, or the element form translation of a type reference.
 The attribute form translation of a type reference is an attribute
 item with the [local name] "type".  The [normalized value] of this
 attribute item is a qualified name for the expanded name of the
 referenced type definition (see Section 5.1).  The attribute form
 translation SHALL NOT be used if this expanded name is not distinct
 with respect to the current module and the modules referenced by its
 <import> element items (see Section 5.1).
 The element form translation of a type reference is an element item
 with the [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An attribute item with the [local name] "ref" SHALL be added
 to the [attributes] of the <type> element item.  The
 [normalized value] of this attribute item is a qualified name for the
 expanded name of the referenced type definition.  If this expanded
 name is not distinct with respect to the current module and the
 modules referenced by its <import> element items, then an attribute
 item with the [local name] "context" SHALL be added to the

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 [attributes] of the <type> element item; otherwise, if the module
 containing the referenced type definition has a schema identity URI,
 then an attribute item with the [local name] "context" MAY be added
 to the [attributes] of the <type> element item.  The
 [normalized value] of this attribute item is the schema identity URI
 of the module containing the type definition referenced by the
 DefinedType.
    Aside: If a reference name is not distinct, then the module
    containing the referenced definition must have a schema identity
    URI (see Section 5.1).
 An attribute item with the [local name] "embedded" and
 [normalized value] "false" or "0" MAY be added to the [attributes] of
 the <type> element item.
 The translation of the DefinedType is the same whether the type
 definition is referenced by a typereference or an
 ExternalTypeReference.
 If a DefinedType is subject to a TYPE-REF encoding instruction, then
 the translation of the DefinedType is an element item with the
 [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An attribute item with the [local name] "ref" SHALL be added
 to the [attributes] of the <type> element item.  The
 [normalized value] of this attribute item is the RXER character data
 translation of the QNameValue in the TYPE-REF encoding instruction.
 If a ContextParameter is present in the RefParameters in the TYPE-REF
 encoding instruction, then an attribute item with the [local name]
 "context" SHALL be added to the [attributes] of the <type> element
 item.  The [normalized value] of this attribute item is the string
 value of the AnyURIValue in the ContextParameter.  An attribute item
 with the [local name] "embedded" and [normalized value] "true" or "1"
 SHALL be added to the [attributes] of the <type> element item.
    Aside: The embedded attribute item indicates whether a type is
    directly referenced as a DefinedType or indirectly referenced
    through a TYPE-REF encoding instruction.  An ASN.1 type can be
    referenced either way.  Type definitions in other schema languages
    cannot be directly referenced.
 If a DefinedType is subject to a REF-AS-TYPE encoding instruction,
 then the translation of the DefinedType is an element item with the
 [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An attribute item with the [local name] "elementType" SHALL be
 added to the [attributes] of the <type> element item.  The

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 [normalized value] of this attribute item is the RXER character data
 translation of the NameValue in the REF-AS-TYPE encoding instruction.
 If a ContextParameter is present in the RefParameters in the
 REF-AS-TYPE encoding instruction, then an attribute item with the
 [local name] "context" SHALL be added to the [attributes] of the
 <type> element item.  The [normalized value] of this attribute item
 is the string value of the AnyURIValue in the ContextParameter.
 Example
    CHOICE {
        one    Foo,
        two    [RXER:TYPE-REF
                   { namespace-name "http://www.example.com/PO1",
                     local-name "PurchaseOrderType" }]
               Markup,
        three  [RXER:REF-AS-TYPE "product"
                   CONTEXT "http://www.example.com/inventory"]
               Markup
    }
    <type>
     <choice>
      <element name="one" type="tns:Foo"/>
      <element name="two" xmlns:po="http://www.example.com/PO1">
       <type ref="po:PurchaseOrderType" embedded="true"/>
      </element>
      <element name="three">
       <type elementType="product"
             context="http://www.example.com/inventory"/>
      </element>
     </choice>
    </type>
 If a DefinedType is a DummyReference, ParameterizedType, or
 ParameterizedValueSetType, then the translation of the Type is the
 translation of that DummyReference, ParameterizedType, or
 ParameterizedValueSetType (see Section 13).

6.3. Translation of Built-in Types

 If a Type is a BuiltinType or ReferencedType that is one of the
 productions in Table 1 in Section 5 of the specification for RXER
 [RXER], then the translation of the Type is either the attribute form
 or element form translation of that type.

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 The attribute form translation of a Type that is a BuiltinType or
 ReferencedType that is one of the productions in Table 1 is an
 attribute item with the [local name] "type".  The [normalized value]
 of this attribute item is a qualified name for the expanded name of
 the built-in type (see Section 5 of the specification for RXER
 [RXER]).
 The element form translation of a Type that is a BuiltinType or
 ReferencedType that is one of the productions in Table 1 is an
 element item with the [local name] "type".  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <type> element item.  An attribute item with the [local name] "ref"
 SHALL be added to the [attributes] of the <type> element item.  The
 [normalized value] of this attribute item is a qualified name for the
 expanded name of the built-in type.
 Example
    BOOLEAN
    <type ref="asnx:BOOLEAN"/>
 Usually the translator is free to choose either the attribute form or
 element form translation for a Type; however, in some contexts
 attribute forms for a Type are explicitly disallowed.

6.4. BitStringType Translation

 The translation of a BitStringType with a NamedBitList is an element
 item with the [local name] "type".  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <type> element item.  An element item with the [local name]
 "namedBitList" SHALL be appended to the [children] of the <type>
 element item.  The translation of each NamedBit in the NamedBitList
 SHALL be appended to the [children] of the <namedBitList> element
 item.
 The translation of a NamedBit is an element item with the
 [local name] "namedBit".  An attribute item with the [local name]
 "name" SHALL be added to the [attributes] of the <namedBit> element
 item.  If the BitStringType is subject to a VALUES encoding
 instruction, then the [normalized value] of this attribute item is
 the replacement name [RXEREI] for the identifier in the NamedBit;
 otherwise, it is the identifier in the NamedBit.  If the
 BitStringType is subject to a VALUES encoding instruction and the
 reduction of the replacement name (see Section 6.1) is not the same
 as the identifier, then an attribute item with the [local name]
 "identifier" SHALL be added to the [attributes] of the <namedBit>

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 element item; otherwise, an attribute item with the [local name]
 "identifier" MAY be added to the [attributes] of the <namedBit>
 element item.  The [normalized value] of this attribute item is the
 identifier in the NamedBit.  An attribute item with the [local name]
 "bit" SHALL be added to the [attributes] of the <namedBit> element
 item.  The [normalized value] of this attribute item is the digit
 string representation of the integer value of the number or
 DefinedValue in the NamedBit.
 Examples
    BIT STRING { zero(0), one(1), two(2) }
    <type>
     <namedBitList>
      <namedBit name="zero" bit="0"/>
      <namedBit name="one" bit="1"/>
      <namedBit name="two" bit="2"/>
     </namedBitList>
    </type>
    [RXER:VALUES ALL CAPITALIZED, wednesday AS "Midweek"]
        BIT STRING {
            monday(0), tuesday(1), wednesday(2),
            thursday(3), friday(4)
        }
    <type>
     <namedBitList>
      <namedBit name="Monday" bit="0"/>
      <namedBit name="Tuesday" bit="1"/>
      <namedBit name="Midweek" identifier="wednesday" bit="2"/>
      <namedBit name="Thursday" bit="3"/>
      <namedBit name="Friday" bit="4"/>
     </namedBitList>
    </type>

6.5. IntegerType Translation

 The translation of an IntegerType with a NamedNumberList is an
 element item with the [local name] "type".  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <type> element item.  An element item with the [local name]
 "namedNumberList" SHALL be appended to the [children] of the <type>
 element item.  The translation of each NamedNumber in the
 NamedNumberList SHALL be appended to the [children] of the
 <namedNumberList> element item.

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 The translation of a NamedNumber is an element item with the
 [local name] "namedNumber".  An attribute item with the [local name]
 "name" SHALL be added to the [attributes] of the <namedNumber>
 element item.  If the IntegerType is subject to a VALUES encoding
 instruction, then the [normalized value] of this attribute item is
 the replacement name [RXEREI] for the identifier in the NamedNumber;
 otherwise, it is the identifier in the NamedNumber.  If the
 IntegerType is subject to a VALUES encoding instruction and the
 reduction of the replacement name (see Section 6.1) is not the same
 as the identifier, then an attribute item with the [local name]
 "identifier" SHALL be added to the [attributes] of the <namedNumber>
 element item; otherwise, an attribute item with the [local name]
 "identifier" MAY be added to the [attributes] of the <namedNumber>
 element item.  The [normalized value] of this attribute item is the
 identifier in the NamedNumber.  An attribute item with the
 [local name] "number" SHALL be added to the [attributes] of the
 <namedNumber> element item.  The [normalized value] of this attribute
 item is the digit string representation of the integer value of the
 SignedNumber or DefinedValue in the NamedNumber.
 Examples
    INTEGER { nothing(0), a-little(1), a-lot(100) }
    <type>
     <namedNumberList>
      <namedNumber name="nothing" number="0"/>
      <namedNumber name="a-little" number="1"/>
      <namedNumber name="a-lot" number="100"/>
     </namedNumberList>
    </type>
    [RXER:VALUES ALL CAPITALIZED, very-high AS "DANGEROUS"]
        INTEGER { low(25), medium(50), high(75), very-high(100) }
    <type>
     <namedNumberList>
      <namedNumber name="Low" number="25"/>
      <namedNumber name="Medium" number="50"/>
      <namedNumber name="High" number="75"/>
      <namedNumber name="DANGEROUS" identifier="very-high"
                   number="100"/>
     </namedNumberList>
    </type>

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6.6. EnumeratedType Translation

 The translation of an EnumeratedType is an element item with the
 [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An element item with the [local name] "enumerated" SHALL be
 appended to the [children] of the <type> element item.  The
 translation of each EnumerationItem nested in the RootEnumeration in
 the Enumerations instance in the EnumeratedType SHALL be appended to
 the [children] of the <enumerated> element item.
 If an ellipsis ("...") is present in the Enumerations instance, then
 an element item with the [local name] "extension" SHALL be appended
 to the [children] of the <enumerated> element item and the
 translation of the ExceptionSpec (possibly empty) SHALL be added to
 the [children] of the <extension> element item.  If an
 AdditionalEnumeration is present in the Enumerations instance, then
 the translation of each EnumerationItem nested in the
 AdditionalEnumeration SHALL be appended to the [children] of the
 <extension> element item.
 The translation of an EnumerationItem is an element item with the
 [local name] "enumeration".
 If the EnumerationItem is of the "identifier" form, then an attribute
 item with the [local name] "name" SHALL be added to the [attributes]
 of the <enumeration> element item.  If the EnumeratedType is subject
 to a VALUES encoding instruction, then the [normalized value] of this
 attribute item is the replacement name [RXEREI] for the identifier;
 otherwise, it is the identifier.  If the EnumeratedType is subject to
 a VALUES encoding instruction and the reduction of the replacement
 name (see Section 6.1) is not the same as the identifier, then an
 attribute item with the [local name] "identifier" SHALL be added to
 the [attributes] of the <enumeration> element item; otherwise, an
 attribute item with the [local name] "identifier" MAY be added to the
 [attributes] of the <enumeration> element item.  The
 [normalized value] of this attribute item is the identifier.
 If the EnumerationItem is of the "NamedNumber" form, then an
 attribute item with the [local name] "name" SHALL be added to the
 [attributes] of the <enumeration> element item.  If the
 EnumeratedType is subject to a VALUES encoding instruction, then the
 [normalized value] of this attribute item is the replacement name
 [RXEREI] for the identifier in the NamedNumber; otherwise, it is the
 identifier in the NamedNumber.  If the EnumeratedType is subject to a
 VALUES encoding instruction and the reduction of the replacement name
 is not the same as the identifier, then an attribute item with the
 [local name] "identifier" SHALL be added to the [attributes] of the

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 <enumeration> element item; otherwise, an attribute item with the
 [local name] "identifier" MAY be added to the [attributes] of the
 <enumeration> element item.  The [normalized value] of this attribute
 item is the identifier in the NamedNumber.  An attribute item with
 the [local name] "number" SHALL be added to the [attributes] of the
 <enumeration> element item.  The [normalized value] of this attribute
 item is the digit string representation of the integer value of the
 SignedNumber or DefinedValue in the NamedNumber.
 Examples
    ENUMERATED { red(0), green(1), ..., blue(2) }
    <type>
     <enumerated>
      <enumeration name="red" number="0"/>
      <enumeration name="green" number="1"/>
      <extension>
       <enumeration name="blue" number="2"/>
      </extension>
     </enumerated>
    </type>
    [RXER:VALUES ALL CAPITALIZED, red AS "Crimson"]
        ENUMERATED { red, yellow, green, blue }
    <type>
     <enumerated>
      <enumeration name="Crimson" identifier="red"/>
      <enumeration name="Yellow"/>
      <enumeration name="Green"/>
      <enumeration name="Blue"/>
     </enumerated>
    </type>

6.7. PrefixedType Translation

 The translation of a PrefixedType [X.680-1] that is a TaggedType is
 either the short form translation (Section 6.7.1) or long form
 translation (Section 6.7.2) of the TaggedType.
    Aside: The short form translation is provided because TaggedType
    notation is heavily used in existing ASN.1 specifications.  The
    long form translation has the same structure as the translation of
    an EncodingPrefixedType and can be simplified where there is a
    series of nested PrefixedType instances.

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 If a PrefixedType is an EncodingPrefixedType and the
 EncodingReference is RXER, or the EncodingReference is empty and the
 default encoding reference [X.680-1] for the module is RXER, then the
 translation of the PrefixedType is the translation of the Type in the
 EncodingPrefixedType.
    Aside: This is not suggesting that RXER encoding instructions are
    ignored.  Encoding instructions for RXER are not explicitly
    represented in ASN.X, but rather affect how an ASN.1 module is
    translated into an ASN.X module (since the content of an ASN.X
    module is also the RXER encoding of an abstract value of the
    ModuleDefinition ASN.1 type in Appendix A).  The individual
    effects of RXER encoding instructions on the translation are
    addressed in other parts of this specification.  Encoding
    instructions for other encoding rules have explicit
    representations in ASN.X.
 If a PrefixedType is an EncodingPrefixedType and the
 EncodingReference is not RXER, or the EncodingReference is empty and
 the default encoding reference for the module is not RXER, then the
 translation of the PrefixedType is an element item with the
 [local name] "prefixed".  The translation of the EncodingPrefix in
 the EncodingPrefixedType SHALL be added to the [children] of the
 <prefixed> element item.
 If the EncodingReference of an EncodingPrefix is not empty, then the
 translation of the EncodingPrefix is an element item with the
 encodingreference in the EncodingReference as the [local name].  The
 translation of the EncodingInstruction in the EncodingPrefix SHALL be
 added to the [children] of this element item.
 If the EncodingReference of an EncodingPrefix is empty, then the
 translation of the EncodingPrefix is an element item with the default
 encoding reference for the module as the [local name].  The
 translation of the EncodingInstruction in the EncodingPrefix SHALL be
 added to the [children] of this element item.
 The EncodingInstruction notation is different for each set of
 encoding instructions, and their translations into ASN.X are
 specified in separate documents [GSEREIT][XEREIT].  At the time of
 writing, only three sets of encoding instructions have been defined
 (for RXER [RXEREI], GSER [GSEREI], and EXTENDED-XER [X.693-1]).
 If the child <type> element item of a <prefixed> element item has no
 attribute items and has a child <prefixed> element item, then that
 child <type> element item MAY be replaced by the [children] and
 [attributes] of the inner <prefixed> element item.  Note that the
 long form translation of a TaggedType is also eligible for this

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 rewriting step.  This rewriting step MAY be applied to the result of
 a previous rewriting step if the necessary condition still holds.
 Example
    These three definitions are equivalent.
    [XER:ATTRIBUTE] [XER:USE-UNION] [GSER:CHOICE-OF-STRINGS] CHOICE {
        one  PrintableString,
        two  UTF8String
    }
    <type>
     <prefixed>
      <XER><attribute/></XER>
      <type>
       <prefixed>
        <XER><useUnion/></XER>
        <type>
         <prefixed>
          <GSER><choiceOfStrings/></GSER>
          <type>
           <choice>
            <element name="one" type="asnx:PrintableString"/>
            <element name="two" type="asnx:UTF8String"/>
           </choice>
          </type>
         </prefixed>
        </type>
       </prefixed>
      </type>
     </prefixed>
    </type>
    <type>
     <prefixed>
      <XER><attribute/></XER>
      <XER><useUnion/></XER>
      <GSER><choiceOfStrings/></GSER>
      <type>
       <choice>
        <element name="one" type="asnx:PrintableString"/>
        <element name="two" type="asnx:UTF8String"/>
       </choice>
      </type>
     </prefixed>
    </type>

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6.7.1. Short Form TaggedType Translation

 The short form translation of a TaggedType is an element item with
 the [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An element item with the [local name] "tagged" SHALL be
 appended to the [children] of the <type> element item.
 If the Class in the Tag in the TaggedType is not empty, then an
 attribute item with the [local name] "tagClass" SHALL be added to the
 [attributes] of the <tagged> element item.  The [normalized value] of
 this attribute item is the Class of the Tag with all letters
 downcased, i.e., either "universal", "application", or "private".
 An attribute item with the [local name] "number" SHALL be added to
 the [attributes] of the <tagged> element item.  The
 [normalized value] of this attribute item is the digit string
 representation of the integer value of the number or DefinedValue in
 the ClassNumber in the Tag.
 If the Tag is immediately followed by the "IMPLICIT" keyword, then an
 attribute item with the [local name] "tagging" and [normalized value]
 "implicit" SHALL be added to the [attributes] of the <tagged> element
 item.
 If the Tag is immediately followed by the "EXPLICIT" keyword, then an
 attribute item with the [local name] "tagging" and [normalized value]
 "explicit" SHALL be added to the [attributes] of the <tagged> element
 item.
 The translation of the Type in the TaggedType SHALL be added to the
 [children] or [attributes] of the <tagged> element item.
 Examples
    [0] INTEGER
    <type>
     <tagged number="0" type="asnx:INTEGER"/>
    </type>
    [APPLICATION 10] IMPLICIT BOOLEAN
    <type>
     <tagged tagClass="application" number="10" tagging="implicit"
             type="asnx:BOOLEAN"/>
    </type>

Legg Experimental [Page 28] RFC 4912 Abstract Syntax Notation X July 2007

6.7.2. Long Form TaggedType Translation

 The long form translation of a TaggedType is an element item with the
 [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An element item with the [local name] "prefixed" SHALL be
 appended to the [children] of the <type> element item.  The
 translation of the Tag in the TaggedType SHALL be added to the
 [children] of the <prefixed> element item.
 The translation of a Tag is an element item with the [local name]
 "TAG".
 If the Class of the Tag is not empty, then an attribute item with the
 [local name] "tagClass" SHALL be added to the [attributes] of the
 <TAG> element item.  The [normalized value] of this attribute item is
 the Class of the Tag with all letters downcased, i.e., either
 "universal", "application", or "private".
 An attribute item with the [local name] "number" SHALL be added to
 the [attributes] of the <TAG> element item.  The [normalized value]
 of this attribute item is the digit string representation of the
 integer value of the number or DefinedValue in the ClassNumber in the
 Tag.
 If the Tag is immediately followed by the "IMPLICIT" keyword, then an
 attribute item with the [local name] "tagging" and [normalized value]
 "implicit" SHALL be added to the [attributes] of the <TAG> element
 item.
 If the Tag is immediately followed by the "EXPLICIT" keyword, then an
 attribute item with the [local name] "tagging" and [normalized value]
 "explicit" SHALL be added to the [attributes] of the <TAG> element
 item.
 The translation of the Type in the TaggedType SHALL be added to the
 [children] or [attributes] of the <prefixed> element item.
 Examples
    [0] INTEGER
    <type>
     <prefixed type="asnx:INTEGER">
      <TAG number="0"/>
     </prefixed>
    </type>

Legg Experimental [Page 29] RFC 4912 Abstract Syntax Notation X July 2007

    [APPLICATION 10] IMPLICIT BOOLEAN
    <type>
     <prefixed type="asnx:BOOLEAN">
      <TAG tagClass="application" number="10" tagging="implicit"/>
     </prefixed>
    </type>

6.8. SelectionType Translation

 The translation of a SelectionType is an element item with the
 [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An element item with the [local name] "selection" SHALL be
 appended to the [children] of the <type> element item.
 The identifier in a SelectionType identifies a NamedType in the
 definition of the Type in the SelectionType.  The translation of that
 NamedType will be an element item with the [local name] either
 "attribute", "element", "component", "group", or "member".  An
 attribute item with the same [local name] as the translation of the
 NamedType SHALL be added to the [attributes] of the <selection>
 element item.  The [normalized value] of this attribute item is a
 qualified name for the expanded name of the NamedType [RXEREI].
 The translation of the Type in the SelectionType SHALL be added to
 the [children] or [attributes] of the <selection> element item.
 Examples
    field1 < MyChoiceType
    <type>
     <selection element="field1" type="tns:MyChoiceType"/>
    </type>
    field2 < CHOICE {
        field2  [RXER:ATTRIBUTE][RXER:NAME AS "field-two"] INTEGER
    }
    <type>
     <selection attribute="field-two">
      <type>
       <choice>
        <attribute name="field-two" identifier="field2"
                   type="asnx:INTEGER"/>
       </choice>
      </type>

Legg Experimental [Page 30] RFC 4912 Abstract Syntax Notation X July 2007

     </selection>
    </type>

6.9. InstanceOfType Translation

 The translation of an InstanceOfType is an element item with the
 [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An element item with the [local name] "instanceOf" SHALL be
 appended to the [children] of the <type> element item.  The
 translation of the DefinedObjectClass in the InstanceOfType SHALL be
 added to the [children] or [attributes] of the <instanceOf> element
 item.
 Example
    INSTANCE OF TYPE-IDENTIFIER
    <type>
     <instanceOf class="asnx:TYPE-IDENTIFIER"/>
    </type>

6.10. ObjectClassFieldType Translation

 The translation of an ObjectClassFieldType is an element item with
 the [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An element item with the [local name] "fromClass" SHALL be
 appended to the [children] of the <type> element item.  The
 translation of the DefinedObjectClass in the ObjectClassFieldType
 SHALL be added to the [children] or [attributes] of the <fromClass>
 element item.  The translation of the FieldName (see Section 9.2.6)
 in the ObjectClassFieldType SHALL be added to the [children] or
 [attributes] of the <fromClass> element item.
 Example
    OPERATION.&Linked.&ArgumentType
    <type>
     <fromClass class="tns:OPERATION"
                fieldName="Linked/ArgumentType"/>
    </type>

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6.11. TypeFromObject and ValueSetFromObjects Translation

 The translation of a TypeFromObject or ValueSetFromObjects is an
 element item with the [local name] "type".  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <type> element item.  An element item with the [local name]
 "fromObjects" SHALL be appended to the [children] of the <type>
 element item.
 The translation of the ReferencedObjects instance in the
 TypeFromObject or ValueSetFromObjects SHALL be added to the
 [children] or [attributes] of the <fromObjects> element item.
 The translation of the FieldName in the TypeFromObject or
 ValueSetFromObjects SHALL be added to the [children] or [attributes]
 of the <fromObjects> element item.
 Example
    invertMatrix.&Errors.&errorCode
    <type>
     <fromObjects object="tns:invertMatrix"
                  fieldName="Errors/errorCode"/>
    </type>

6.12. Translation of Combining Types

 This section details the translation of the ASN.1 combining types:
 SET, SEQUENCE, CHOICE, SET OF, and SEQUENCE OF.  The combining type
 definitions all make use of the NamedType notation.

6.12.1. NamedType Translation

 A NamedType is translated in one of three ways depending on the
 context.  These are the normal translation, the member translation,
 and the item translation.  These translations are not
 interchangeable.  One of the three will be explicitly invoked as part
 of the translation of an enclosing combining type.
 The normal translation of a NamedType is an element item with the
 [local name] determined as follows:
 (1) if the NamedType is subject to an ATTRIBUTE or ATTRIBUTE-REF
     encoding instruction, or subject to a COMPONENT-REF encoding
     instruction that references a top-level NamedType that is subject
     to an ATTRIBUTE encoding instruction, then the [local name] is
     "attribute",

Legg Experimental [Page 32] RFC 4912 Abstract Syntax Notation X July 2007

 (2) else if the NamedType is subject to a GROUP encoding instruction,
     then the [local name] is "group",
 (3) else if the NamedType is subject to a SIMPLE-CONTENT encoding
     instruction, then the [local name] is "simpleContent",
 (4) otherwise, the [local name] is "element" or "component"
     (translator's choice).
    Aside: The local names "element" and "component" are synonymous.
    The "component" alternative is offered for specifying applications
    that don't use RXER (except for the ASN.X specification itself, of
    course), where referring to parts of an encoding as elements would
    seem incongruous.
 The member translation of a NamedType is an element item with the
 [local name] "member".
 The item translation of a NamedType is an element item with the
 [local name] "item".
    Aside: A Namedtype for which the member or item translation is
    invoked will never be subject to an ATTRIBUTE, ATTRIBUTE-REF,
    COMPONENT-REF, GROUP, SIMPLE-CONTENT, or TYPE-AS-VERSION encoding
    instruction.  These encoding instructions are also mutually
    exclusive [RXEREI].
 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <attribute>, <element>, <component>, <group>,
 <item>, <member>, or <simpleContent> element item.
 If a NamedType is subject to a TYPE-AS-VERSION encoding instruction,
 then an attribute item with the [local name] "typeAsVersion" and
 [normalized value] "true" or "1" SHALL be added to the <element> or
 <component> element item.  For the normal translation, if a NamedType
 is not subject to an ATTRIBUTE, ATTRIBUTE-REF, COMPONENT-REF, GROUP,
 SIMPLE-CONTENT, or TYPE-AS-VERSION encoding instruction, then an
 attribute item with the [local name] "typeAsVersion" and
 [normalized value] "false" or "0" MAY be added to the <element> or
 <component> element item.
 For the normal, member, and item translations, if a NamedType is not
 subject to an ATTRIBUTE-REF, COMPONENT-REF, ELEMENT-REF, or
 REF-AS-ELEMENT encoding instruction, then an attribute item with the
 [local name] "name" SHALL be added to the [attributes] of the
 <attribute>, <element>, <component>, <group>, <item>, <member>, or

Legg Experimental [Page 33] RFC 4912 Abstract Syntax Notation X July 2007

 <simpleContent> element item.  The [normalized value] of this
 attribute item is the local name of the expanded name of the
 NamedType [RXEREI].
    Aside: If there are no NAME, ATTRIBUTE-REF, COMPONENT_REF,
    ELEMENT-REF or REF-AS-ELEMENT encoding instructions, then the
    local name of the expanded name of a NamedType is the same as the
    identifier in the NamedType.
 If the reduction of the local name (an NCName) of the expanded name
 of a NamedType is not the same as the identifier in the NamedType,
 then an attribute item with the [local name] "identifier" SHALL be
 added to the [attributes] of the <attribute>, <element>, <component>,
 <group>, <item>, <member>, or <simpleContent> element item;
 otherwise, an attribute item with the [local name] "identifier" MAY
 be added to the [attributes] of the aforementioned element item.  The
 [normalized value] of this attribute item is the identifier in the
 NamedType.
    Aside: The identifier attribute is not contingent on there being a
    name attribute.  That is, an element item can have an identifier
    attribute item without having a name attribute item.
 If a NamedType is subject to a COMPONENT-REF encoding instruction,
 then an attribute item with the [local name] "ref" SHALL be added to
 the [attributes] of the <attribute>, <element>, or <component>
 element item.  The [normalized value] of this attribute item is a
 qualified name for the expanded name of the top-level NamedType
 referenced by the encoding instruction.  If the expanded name is not
 distinct with respect to the current module and the modules
 referenced by its <import> element items (see Section 5.1), then an
 attribute item with the [local name] "context" SHALL be added to the
 [attributes] of the <attribute>, <element>, or <component> element
 item; otherwise, if the module containing the referenced top-level
 NamedType has a schema identity URI, then an attribute item with the
 [local name] "context" MAY be added to the [attributes] of the
 <attribute>, <element>, or <component> element item.  The
 [normalized value] of this attribute item is the schema identity URI
 of the module containing the referenced top-level NamedType.
    Aside: If an expanded name is not distinct, then the module
    containing the referenced top-level NamedType must have a schema
    identity URI (see Section 5.1).
 If a NamedType is subject to a COMPONENT-REF encoding instruction,
 then an attribute item with the [local name] "embedded" and
 [normalized value] "false" or "0" MAY be added to the [attributes] of
 the <attribute>, <element>, or <component> element item.

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 If a NamedType is subject to an ATTRIBUTE-REF or ELEMENT-REF encoding
 instruction, then an attribute item with the [local name] "ref" SHALL
 be added to the [attributes] of the <attribute>, <element>, or
 <component> element item.  The [normalized value] of this attribute
 item is the RXER character data translation of the QNameValue in the
 encoding instruction.  An attribute item with the [local name]
 "embedded" and [normalized value] "true" or "1" SHALL be added to the
 [attributes] of the <attribute>, <element>, or <component> element
 item.
 If a NamedType is subject to a REF-AS-ELEMENT encoding instruction,
 then an attribute item with the [local name] "elementType" SHALL be
 added to the [attributes] of the <element> or <component> element
 item.  The [normalized value] of this attribute item is the RXER
 character data translation of the NameValue in the REF-AS-ELEMENT
 encoding instruction.  If a Namespace is present in the
 REF-AS-ELEMENT encoding instruction, then an attribute item with the
 [local name] "namespace" SHALL be added to the [attributes] of the
 <element> or <component> element item.  The [normalized value] of
 this attribute item is the string value of the AnyURIValue in the
 Namespace.
 If a ContextParameter is present in the RefParameters in the
 ATTRIBUTE-REF, ELEMENT-REF, or REF-AS-ELEMENT encoding instruction,
 then an attribute item with the [local name] "context" SHALL be added
 to the [attributes] of the <attribute>, <element>, or <component>
 element item.  The [normalized value] of this attribute item is the
 string value of the AnyURIValue in the ContextParameter.
 If a NamedType is subject to both an ATTRIBUTE encoding instruction
 and a VERSION-INDICATOR encoding instruction, then an attribute item
 with the [local name] "versionIndicator" and [normalized value]
 "true" or "1" SHALL be added to the <attribute> element item.  If a
 NamedType is subject to an ATTRIBUTE encoding instruction and not
 subject to a VERSION-INDICATOR encoding instruction, then an
 attribute item with the [local name] "versionIndicator" and
 [normalized value] "false" or "0" MAY be added to the <attribute>
 element item.
 If a NamedType is not subject to an ATTRIBUTE-REF, COMPONENT-REF,
 ELEMENT-REF, or REF-AS-ELEMENT encoding instruction, then the
 translation of the Type in the NamedType SHALL be added to the
 [children] or [attributes] of the <attribute>, <element>,
 <component>, <group>, <item>, <member>, or <simpleContent> element
 item.

Legg Experimental [Page 35] RFC 4912 Abstract Syntax Notation X July 2007

 If a NamedType is subject to an ATTRIBUTE-REF, COMPONENT-REF,
 ELEMENT-REF, or REF-AS-ELEMENT encoding instruction, then the
 translation of each EncodingPrefix (Section 6.7) and Tag
 (Section 6.7.2) textually within the NamedType SHALL be added in
 order to the [children] of the <attribute>, <element>, or <component>
 element item.
 Example
    CHOICE {
        one    INTEGER,
        two    [RXER:ATTRIBUTE] BOOLEAN,
        three  [RXER:ATTRIBUTE-REF
                   { namespace-name "http://www.example.com/schema",
                     local-name "foo" }]
               UTF8String,
        bar    [RXER:ELEMENT-REF
                   { namespace-name "http://www.example.com/schema",
                     local-name "bar" }]
               Markup,
        five   [0] [RXER:REF-AS-ELEMENT "product"
                   CONTEXT "http://www.example.com/inventory"]
               Markup,
        six    [RXER:GROUP] MySequence
    }
    <type>
     <choice xmlns:ex="http://www.example.com/schema">
      <element name="one" type="asnx:INTEGER"/>
      <attribute name="two" type="asnx:BOOLEAN"/>
      <attribute ref="ex:foo" identifier="three" embedded="true"/>
      <element ref="ex:bar" embedded="true"/>
      <element elementType="product"
               context="http://www.example.com/inventory"
               identifier="five">
       <TAG number="0"/>
      </element>
      <group name="six" type="tns:MySequence"/>
     </choice>
    </type>

6.12.2. SequenceType Translation

 The translation of a SequenceType is an element item with the
 [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An element item with the [local name] "sequence" SHALL be
 appended to the [children] of the <type> element item.  The

Legg Experimental [Page 36] RFC 4912 Abstract Syntax Notation X July 2007

 translation of each ComponentType nested in the ComponentTypeList in
 the initial RootComponentTypeList, if present, SHALL be appended to
 the [children] of the <sequence> element item.
 If an ExtensionAndException is present, then an element item with the
 [local name] "extension" SHALL be appended to the [children] of the
 <sequence> element item.  If an ExceptionSpec is present in the
 ExtensionAndException, then the translation of the ExceptionSpec
 (possibly empty) SHALL be added to the [children] of the <extension>
 element item.
 If an ExtensionAdditions instance is present, then the translation of
 each ExtensionAdditionGroup or ComponentType nested in the
 ExtensionAdditions (if any) SHALL be appended to the [children] of
 the <extension> element item.
 If an ExtensionEndMarker is present, then the translation of each
 ComponentType nested in the ComponentTypeList in the final
 RootComponentTypeList SHALL be appended to the [children] of the
 <sequence> element item.
 The translation of an ExtensionAdditionGroup is an element item with
 the [local name] "extensionGroup".  If the VersionNumber in the
 ExtensionAdditionGroup is not empty, then an attribute item with the
 [local name] "version" SHALL be added to the [attributes] of the
 <extensionGroup> element item.  The [normalized value] of this
 attribute item is the number in the VersionNumber.  The translation
 of each ComponentType nested in the ExtensionAdditionGroup SHALL be
 appended to the [children] of the <extensionGroup> element item.
 The translation of a ComponentType of the "NamedType" form is the
 normal translation of the NamedType.
 The translation of a ComponentType of the "NamedType OPTIONAL" form
 is an element item with the [local name] "optional".  The normal
 translation of the NamedType SHALL be added to the [children] of the
 <optional> element item.
 The translation of a ComponentType of the "NamedType DEFAULT Value"
 form is an element item with the [local name] "optional".  The normal
 translation of the NamedType SHALL be added to the [children] of the
 <optional> element item.  An element item with the [local name]
 "default" SHALL be appended to the [children] of the <optional>
 element item.  The translation of the Value SHALL be added to the
 [children] or [attributes] of the <default> element item.

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 The translation of a ComponentType of the "COMPONENTS OF Type" form
 is an element item with the [local name] "componentsOf".  The
 translation of the Type SHALL be added to the [children] or
 [attributes] of the <componentsOf> element item.
 Example
    SEQUENCE {
        one    INTEGER,
        two    [RXER:ATTRIBUTE] BOOLEAN OPTIONAL,
        ...,
        [[ 2:
            four   NULL
        ]],
        COMPONENTS OF MySequence,
        ...,
        three   PrintableString DEFAULT "third"
    }
    <type>
     <sequence>
      <element name="one" type="asnx:INTEGER"/>
      <optional>
       <attribute name="two" type="asnx:BOOLEAN"/>
      </optional>
      <extension>
       <extensionGroup version="2">
        <element name="four" type="asnx:NULL"/>
       </extensionGroup>
       <componentsOf type="tns:MySequence"/>
      </extension>
      <optional>
       <element name="three" type="asnx:PrintableString"/>
       <default literalValue="third"/>
      </optional>
     </sequence>
    </type>

6.12.3. SetType Translation

 The translation of a SetType follows the same procedure as the
 translation of a SequenceType except that SetType replaces
 SequenceType, "SET" replaces "SEQUENCE", and the [local name] "set"
 is used instead of "sequence".

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6.12.4. ChoiceType Translation

 The translation of a ChoiceType that is not subject to a UNION
 encoding instruction is an element item with the [local name] "type".
 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <type> element item.  An element item with the
 [local name] "choice" SHALL be appended to the [children] of the
 <type> element item.  The normal translation of each NamedType nested
 in the AlternativeTypeList in the RootAlternativeTypeList in the
 AlternativeTypeLists SHALL be appended to the [children] of the
 <choice> element item.
 If an ExtensionAndException is present in the AlternativeTypeLists,
 then an element item with the [local name] "extension" SHALL be
 appended to the [children] of the <choice> element item.  If an
 ExceptionSpec is present in the ExtensionAndException, then the
 translation of the ExceptionSpec (possibly empty) is added to the
 [children] of the <extension> element item.
 If an ExtensionAdditionAlternatives instance is present in the
 AlternativeTypeLists, then the translation of each
 ExtensionAdditionAlternativesGroup or NamedType (if any) nested in
 the ExtensionAdditionAlternatives SHALL be appended in order to the
 [children] of the <extension> element item.  The normal translation
 of the NamedType is used.
 The translation of an ExtensionAdditionAlternativesGroup is an
 element item with the [local name] "extensionGroup".  If the
 VersionNumber in the ExtensionAdditionAlternativesGroup is not empty,
 then an attribute item with the [local name] "version" SHALL be added
 to the [attributes] of the <extensionGroup> element item.  The
 [normalized value] of this attribute item is the number in the
 VersionNumber.  The normal translation of each NamedType nested in
 the AlternativeTypeList in the ExtensionAdditionAlternativesGroup
 SHALL be appended to the [children] of the <extensionGroup> element
 item.

Legg Experimental [Page 39] RFC 4912 Abstract Syntax Notation X July 2007

 Example
    CHOICE {
        one  INTEGER,
        two  [RXER:NAME AS "Two"] BOOLEAN,
        ...,
        [[ 2:
            three  NULL
        ]],
        four  PrintableString,
        ...
    }
    <type>
     <choice>
      <element name="one" type="asnx:INTEGER"/>
      <element name="Two" type="asnx:BOOLEAN"/>
      <extension>
       <extensionGroup version="2">
        <element name="three" type="asnx:NULL"/>
       </extensionGroup>
       <element name="four" type="asnx:PrintableString"/>
      </extension>
     </choice>
    </type>

6.12.5. Translation of UNION Types

 The translation of a ChoiceType that is subject to a UNION encoding
 instruction follows the same procedure as the translation of a
 ChoiceType that is not subject to a UNION encoding instruction except
 that the [local name] "union" is used instead of "choice", and the
 member translation of each NamedType is used instead of the normal
 translation.
 In addition, if the UNION encoding instruction has a PrecedenceList,
 then an attribute item with the [local name] "precedence" SHALL be
 added to the [attributes] of the <union> element item.  The
 [normalized value] of this attribute item is the white space
 separated list of qualified names for the expanded names of the
 NamedType instances [RXEREI] corresponding to the identifiers in the
 PrecedenceList.  A white space separator is one or more of the white
 space characters.

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 Example
    [RXER:UNION PRECEDENCE utf8 visible] CHOICE {
        printable  PrintableString,
        teletex    TeletexString,
        visible    [RXER:NAME AS "ascii"] VisibleString,
        ...,
        utf8       UTF8String
    }
    <type>
     <union precedence="utf8 ascii">
      <member name="printable" type="asnx:PrintableString"/>
      <member name="teletex" type="asnx:TeletexString"/>
      <member name="ascii" identifier="visible"
              type="asnx:VisibleString"/>
      <extension>
       <member name="utf8" type="asnx:UTF8String"/>
      </extension>
     </union>
    </type>

6.12.6. SequenceOfType Translation

 The translation of a SequenceOfType that is not subject to a LIST
 encoding instruction is an element item with the [local name] "type".
 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <type> element item.  An element item with the
 [local name] "sequenceOf" SHALL be appended to the [children] of the
 <type> element item.
 If the SequenceOfType is of the "SEQUENCE OF NamedType" form, then
 the normal translation of the NamedType SHALL be added to the
 [children] of the <sequenceOf> element item.
 If the SequenceOfType is of the "SEQUENCE OF Type" form, then an
 element item with the [local name] "element" or "component"
 (translator's choice) SHALL be added to the [children] of the
 <sequenceOf> element item.  An attribute item with the [local name]
 "name" and [normalized value] "item" SHALL be added to the
 [attributes] of the <element> or <component> element item.  An
 attribute item with the [local name] "identifier" and empty
 [normalized value] SHALL be added to the [attributes] of the
 <element> or <component> element item.  The translation of the Type
 SHALL be added to the [children] or [attributes] of the <element> or
 <component> element item.

Legg Experimental [Page 41] RFC 4912 Abstract Syntax Notation X July 2007

 Examples
    SEQUENCE OF INTEGER
    <type>
     <sequenceOf>
      <element name="item" identifier="" type="asnx:INTEGER"/>
     </sequenceOf>
    </type>
    SEQUENCE OF counter INTEGER
    <type>
     <sequenceOf>
      <element name="counter" type="asnx:INTEGER"/>
     </sequenceOf>
    </type>

6.12.7. Translation of LIST Types

 The translation of a SequenceOfType that is subject to a LIST
 encoding instruction is an element item with the [local name] "type".
 An element item with the [local name] "annotation" MAY be added to
 the [children] of the <type> element item.  An element item with the
 [local name] "list" SHALL be appended to the [children] of the <type>
 element item.  The item translation of the NamedType in the
 SequenceOfType SHALL be added to the [children] of the <list> element
 item.
    Aside: A SequenceOfType is necessarily of the
    "SEQUENCE OF NamedType" form for a LIST encoding instruction.
 Example
    [RXER:LIST] SEQUENCE OF number INTEGER
    <type>
     <list>
      <item name="number" type="asnx:INTEGER"/>
     </list>
    </type>

6.12.8. SetOfType Translation

 The translation of a SetOfType follows the same procedure as the
 translation of a SequenceOfType except that SetOfType replaces
 SequenceOfType, "SET" replaces "SEQUENCE", and the [local name]
 "setOf" is used instead of "sequenceOf".

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6.12.9. Effect of Insertion Encoding Instructions

 If a Type is subject to a NO-INSERTIONS, HOLLOW-INSERTIONS,
 SINGULAR-INSERTIONS, UNIFORM-INSERTIONS, or MULTIFORM-INSERTIONS
 encoding instruction, then an attribute item with the [local name]
 "insertions" SHALL be added to the [attributes] of the <choice>,
 <sequence> or <set> element item in the [children] of the <type>
 element item resulting from the translation of the Type.  The
 [normalized value] of this attribute item is "none" in the case of a
 NO-INSERTIONS encoding instruction, "hollow" in the case of a
 HOLLOW-INSERTIONS encoding instruction, "singular" in the case of a
 SINGULAR-INSERTIONS encoding instruction, "uniform" in the case of a
 UNIFORM-INSERTIONS encoding instruction, and "multiform" in the case
 of a MULTIFORM-INSERTIONS encoding instruction.
 Example
    [NO-INSERTIONS] CHOICE {
        one  [RXER:GROUP] [RXER:SINGULAR-INSERTIONS] CHOICE {
            two  INTEGER,
            ...
        },
        ...
    }
    <type>
     <choice insertions="none">
      <group name="one">
       <type>
        <choice insertions="singular">
         <element name="two" type="asnx:INTEGER"/>
         <extension/>
        </choice>
       </type>
      </group>
      <extension/>
     </choice>
    </type>

6.13. Translation of Constrained Types

 If a ConstrainedType is of the "Type Constraint" form, then the
 translation of the ConstrainedType is an element item with the
 [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An element item with the [local name] "constrained" SHALL be
 appended to the [children] of the <type> element item.  The
 translation of the Type SHALL be added to the [children] or

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 [attributes] of the <constrained> element item.  The translation of
 the Constraint SHALL be added to the [children] of the <constrained>
 element item.
 The translation of a ContainedType that is a TypeWithConstraint is
 the translation of the TypeWithConstraint.
 Definition (simple endpoint):  A LowerEndpoint or UpperEndpoint is a
 simple endpoint if it is closed and its value is "MIN", "MAX", or a
 SignedNumber in an IntegerValue in a BuiltinValue in the Value of the
 endpoint.
 Definition (simple range SizeConstraint): A SizeConstraint is a
 simple range if the Constraint in the SizeConstraint contains only a
 ValueRange (i.e., a ValueRange in a SubtypeElements instance in an
 Elements instance in a lone IntersectionElements instance in a lone
 Intersections instance in a Unions instance in an ElementSetSpec in a
 RootElementSetSpec in an ElementSetSpecs instance without an
 AdditionalElementSetSpec in a SubtypeConstraint in a ConstraintSpec
 in the Constraint) and both endpoints are simple.
 Definition (simple range Constraint): A Constraint is a simple range
 if contains only a SizeConstraint that is a simple range (i.e., a
 simple range SizeConstraint in a SubtypeElements instance in an
 Elements instance in a lone IntersectionElements instance in a lone
 Intersections instance in a Unions instance in an ElementSetSpec in a
 RootElementSetSpec in an ElementSetSpecs instance without an
 AdditionalElementSetSpec in a SubtypeConstraint in a ConstraintSpec
 in the Constraint).
 If the Constraint or SizeConstraint in a TypeWithConstraint is a
 simple range, then the compact translation of the TypeWithConstraint
 MAY be used; otherwise, the full translation of the
 TypeWithConstraint is used.
 The compact translation of a TypeWithConstraint is initially the
 translation of its notional parent type.  If the value of the lower
 endpoint is not "MIN" or "0", then an attribute item with the
 [local name] "minSize" SHALL be added to the [attributes] of the
 <sequenceOf>, <setOf>, or <list> element item resulting from the
 translation of the parent type.  The [normalized value] of this
 attribute item is the value of the lower endpoint.  If the value of
 the lower endpoint is "MIN" or "0", then an attribute item with the
 [local name] "minSize" and [normalized value] "0" MAY be added to the
 [attributes] of the <sequenceOf>, <setOf>, or <list> element item.
 If the value of the upper endpoint is not "MAX", then an attribute
 item with the [local name] "maxSize" SHALL be added to the
 [attributes] of the <sequenceOf>, <setOf>, or <list> element item.

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 The [normalized value] of this attribute item is the value of the
 upper endpoint.
 The full translation of a TypeWithConstraint is an element item with
 the [local name] "type".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <type> element
 item.  An element item with the [local name] "constrained" SHALL be
 appended to the [children] of the <type> element item.  The
 translation of the notional parent type of the TypeWithConstraint
 SHALL be added to the [children] or [attributes] of the <constrained>
 element item.  The translation of the Constraint or SizeConstraint in
 the TypeWithConstraint SHALL be added to the [children] of the
 <constrained> element item.
 Examples
    SEQUENCE (SIZE(1..MAX)) OF number INTEGER
    <type>
     <sequenceOf minSize="1">
      <element name="number" type="asnx:INTEGER"/>
     </sequenceOf>
    </type>
    SEQUENCE SIZE(0..10) OF number INTEGER
    <type>
     <sequenceOf maxSize="10">
      <element name="number" type="asnx:INTEGER"/>
     </sequenceOf>
    </type>
    SEQUENCE SIZE(1..limit) OF number INTEGER
    <type>
     <constrained>
      <type>
       <sequenceOf>
        <element name="number" type="asnx:INTEGER"/>
       </sequenceOf>
      </type>
      <size>
       <range>
        <minInclusive literalValue="1"/>
        <maxInclusive value="tns:limit"/>
       </range>

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      </size>
     </constrained>
    </type>

6.13.1. Constraint Translation

 The translation of a Constraint is the translation of the
 ConstraintSpec in the Constraint followed by the translation of the
 ExceptionSpec (possibly empty) in the Constraint.
 The translation of a ConstraintSpec is the translation of the
 SubtypeConstraint or GeneralConstraint in the ConstraintSpec.
 The translation of a SubtypeConstraint is the translation of the
 ElementSetSpecs in the SubtypeConstraint.
 The translation of a GeneralConstraint [X.682] is the translation of
 the UserDefinedConstraint, TableConstraint, or ContentsConstraint in
 the GeneralConstraint.

6.13.2. UserDefinedConstraint Translation

 The translation of a UserDefinedConstraint is an element item with
 the [local name] "constrainedBy".  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <constrainedBy> element item.  The translation of each
 UserDefinedConstraintParameter in the UserDefinedConstraint SHALL be
 appended to the [children] of the <constrainedBy> element item.
 The translation of a UserDefinedConstraintParameter of the
 "Governor : Value" form is an element item with the [local name]
 "valueParameter".  The translation of the Type in the Governor SHALL
 be added to the [children] or [attributes] of the <valueParameter>
 element item.  The translation of the Value SHALL be added to the
 [children] or [attributes] of the <valueParameter> element item.
 The translation of a UserDefinedConstraintParameter of the
 "Governor : ValueSet" form is an element item with the [local name]
 "valueSetParameter".  The translation of the Type in the Governor
 SHALL be added to the [children] or [attributes] of the
 <valueSetParameter> element item.  The translation of the ValueSet
 SHALL be added to the [children] of the <valueSetParameter> element
 item.
 The translation of a UserDefinedConstraintParameter of the
 "Governor : Object" form is an element item with the [local name]
 "objectParameter".  The translation of the DefinedObjectClass in the
 Governor SHALL be added to the [children] or [attributes] of the

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 <objectParameter> element item.  The translation of the Object SHALL
 be added to the [children] or [attributes] of the <objectParameter>
 element item.
 The translation of a UserDefinedConstraintParameter of the
 "Governor : ObjectSet" form is an element item with the [local name]
 "objectSetParameter".  The translation of the DefinedObjectClass in
 the Governor SHALL be added to the [children] or [attributes] of the
 <objectSetParameter> element item.  The translation of the ObjectSet
 SHALL be added to the [children] or [attributes] of the
 <objectSetParameter> element item.
 The translation of a UserDefinedConstraintParameter that is a Type is
 an element item with the [local name] "typeParameter".  The
 translation of the Type SHALL be added to the [children] or
 [attributes] of the <typeParameter> element item.
 The translation of a UserDefinedConstraintParameter that is a
 DefinedObjectClass is an element item with the [local name]
 "classParameter".  The translation of the DefinedObjectClass SHALL be
 added to the [children] or [attributes] of the <classParameter>
 element item.
 Example
    OCTET STRING
        (CONSTRAINED BY {
            -- contains the hash of the value -- MyType:myValue })
    <type>
     <constrained type="asnx:OCTET-STRING">
      <constrainedBy>
       <annotation> contains the hash of the value </annotation>
       <valueParameter type="tns:MyType" value="tns:myValue"/>
      </constrainedBy>
     </constrained>
    </type>

6.13.3. TableConstraint Translation

 The translation of a TableConstraint that is a SimpleTableConstraint
 is an element item with the [local name] "table".  The translation of
 the ObjectSet in the SimpleTableConstraint SHALL be added to the
 [children] or [attributes] of the <table> element item.
 The translation of a TableConstraint that is a
 ComponentRelationConstraint is an element item with the [local name]
 "table".  The translation of the DefinedObjectSet in the

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 ComponentRelationConstraint SHALL be added to the [children] or
 [attributes] of the <table> element item.  The translation of each
 AtNotation in the ComponentRelationConstraint SHALL be appended to
 the [children] of the <table> element item.
 The translation of an AtNotation is an element item with the
 [local name] "restrictBy".  The [children] property of the
 <restrictBy> element item is set to the sequence of character items
 for the character string formed by the concatenation of zero, one, or
 more "../" strings, one for each Level in the AtNotation (including
 the empty one), followed by a solidus ('/', U+002F) separated list of
 qualified names for the expanded names of the NamedType instances
 [RXEREI] identified by the identifiers in the ComponentIdList in the
 AtNotation.  If a NamedType is subject to an ATTRIBUTE or
 ATTRIBUTE-REF encoding instruction, or subject to a COMPONENT-REF
 encoding instruction that references a top-level NamedType that is
 subject to an ATTRIBUTE encoding instruction, then the qualified name
 for the expanded name is prefixed with the commercial at character
 ('@', U+0040).  Leading and/or trailing white space character items
 MAY be added to the [children] of the <restrictBy> element item.
 White space character items MAY be added immediately before and/or
 after any character item for the solidus character ('/', U+002F).
 Examples
    ERROR.&Type({Errors}{@severity,@...errorId})
    <type>
     <constrained>
      <type>
       <fromClass class="tns:ERROR" fieldName="Type"/>
      </type>
      <table objectset="tns:Errors">
       <restrictBy>severity</restrictBy>
       <restrictBy>../../../errorId</restrictBy>
      </table>
     </constrained>
    </type>
    SEQUENCE {
        id-att  [RXER:NAME AS "ID"] [RXER:ATTRIBUTE]
                    TYPE-IDENTIFIER.&id({AllTypes}),
        value   TYPE-IDENTIFIER.&Type({AllTypes}{@id-att})
    }
    <type>
     <sequence>
      <attribute name="ID" identifier="id-att">

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       <type>
        <constrained>
         <type>
          <fromClass class="asnx:TYPE-IDENTIFIER" fieldName="id"/>
         </type>
         <table objectset="tns:AllTypes"/>
        </constrained>
       </type>
      </attribute>
      <element name="value">
       <type>
        <constrained>
         <type>
          <fromClass class="asnx:TYPE-IDENTIFIER" fieldName="Type"/>
         </type>
         <table objectset="tns:AllTypes">
          <restrictBy>@ID</restrictBy>
         </table>
        </constrained>
       </type>
      </element>
     </sequence>
    </type>
 The <restrictBy> element item is required to be self-contained
 [RXER].
    Aside: An element item is self-contained if all namespace prefixes
    used by the element item and its contents are declared within the
    element item.

6.13.4. ContentsConstraint Translation

 The translation of a ContentsConstraint is an element item with the
 [local name] "contents".
 If the ContentsConstraint is of the "CONTAINING Type" form, then an
 element item with the [local name] "containing" SHALL be added to the
 [children] of the <contents> element item.  The translation of the
 Type SHALL be added to the [children] or [attributes] of the
 <containing> element item.
 If the ContentsConstraint is of the "ENCODED BY Value" form, then an
 element item with the [local name] "encodedBy" SHALL be added to the
 [children] of the <contents> element item.  The translation of the
 Value SHALL be added to the [children] or [attributes] of the
 <encodedBy> element item.

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 If the ContentsConstraint is of the
 "CONTAINING Type ENCODED BY Value" form, then an element item with
 the [local name] "containing" and an element item with the
 [local name] "encodedBy" SHALL be added to the [children] of the
 <contents> element item.  The translation of the Type SHALL be added
 to the [children] or [attributes] of the <containing> element item.
 The translation of the Value SHALL be added to the [children] or
 [attributes] of the <encodedBy> element item.
 Example
    OCTET STRING
        (CONTAINING MyType
         ENCODED BY { joint-iso-itu-t asn1(1) basic-encoding(1) })
    <type>
     <constrained type="asnx:OCTET-STRING">
      <contents>
       <containing type="tns:MyType"/>
       <encodedBy literalValue="2.1.1"/>
      </contents>
     </constrained>
    </type>

6.13.5. ExceptionSpec Translation

 The translation of an empty ExceptionSpec is empty.
 The translation of a non-empty ExceptionSpec is an element item with
 the [local name] "exception".
 If the ExceptionIdentification in a non-empty ExceptionSpec is a
 SignedNumber, then the translation of a notional INTEGER Type SHALL
 be added to the [children] or [attributes] of the <exception> element
 item, and the translation of a notional Value of the INTEGER type
 with the SignedNumber as its IntegerValue SHALL be added to the
 [children] or [attributes] of the <exception> element item.
 If the ExceptionIdentification in a non-empty ExceptionSpec is a
 DefinedValue, then the translation of a notional INTEGER Type SHALL
 be added to the [children] or [attributes] of the <exception> element
 item, and the translation of the DefinedValue SHALL be added to the
 [children] or [attributes] of the <exception> element item.

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 If the ExceptionIdentification in a non-empty ExceptionSpec is of the
 "Type : Value" form, then the translation of the Type SHALL be added
 to the [children] or [attributes] of the <exception> element item,
 and the translation of the Value SHALL be added to the [children] or
 [attributes] of the <exception> element item.
 Examples
    !10
    <exception type="asnx:INTEGER" literalValue="10"/>
    !myValue
    <exception type="asnx:INTEGER" value="tns:myValue"/>
    !PrintableString:"failure"
    <exception type="asnx:PrintableString" literalValue="failure"/>

7. Translation of Values

 A Value in an ASN.1 specification is a mix of literal values (e.g.,
 numbers and character strings) and notations for referencing defined
 values.  Likewise, the ASN.X translation of a Value is a mix of
 markup for literal values and markup for referencing notations
 (notational values).  A Value is categorized by the following
 definitions.
 Definition (literal value): A Value is a literal value if and only if
 it is not a notational value.
 Definition (notational value): A Value is a notational value if and
 only if:
 (1) the Value is a BuiltinValue, and
     (a) the BuiltinValue is a TaggedValue and the Value in the
         TaggedValue is a notational value, or
     (b) the BuiltinValue is a SequenceValue or SetValue with a
         ComponentValueList that contains a NamedValue where the Value
         in the NamedValue is a notational value and the translation
         of the corresponding NamedType (from the governing type of
         the outer Value) is not an <element> or <component> element
         item, or

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     (c) the BuiltinValue is a ChoiceValue where the Value of the
         ChoiceValue is a notational value and the translation of the
         NamedType corresponding to the identifier in the ChoiceValue
         is not an <element> or <component> element item, or
     (d) the BuiltinValue is a SequenceOfValue or SetOfValue with a
         NamedValueList that contains a NamedValue where the Value of
         the NamedValue is a notational value and the translation of
         the corresponding NamedType (from the governing type of the
         outer Value) is not an <element> or <component> element item,
         or
 (2) the Value is a ReferencedValue, and
     (a) the ReferencedValue is a ValueFromObject, or
     (b) the ReferencedValue is a DefinedValue, and
         (i)   the DefinedValue is a valuereference (not a
               DummyReference) or an ExternalValueReference, or
         (ii)  the DefinedValue is a DummyReference or
               ParameterizedValue and the substitute definition for
               the DummyReference or ParameterizedValue (see
               Section 13) is a notational value, or
         (iii) the DefinedValue is a DummyReference or
               ParameterizedValue where the translation of the
               DummyReference or ParameterizedValue will use a fully
               expanded reference (see Section 13), or
 (3) the Value is an ObjectClassFieldValue, and
     (a) the ObjectClassFieldValue is an OpenTypeFieldVal, or
     (b) the ObjectClassFieldValue is a FixedTypeFieldVal, and
         (i)  the FixedTypeFieldVal is a BuiltinValue that satisfies
              case (1), or
         (ii) the FixedTypeFieldVal is a ReferencedValue that
              satisfies case (2).
 A literal value that is a BuiltinValue that is a SequenceValue,
 SetValue, ChoiceValue, SequenceOfValue, or SetOfValue MAY be
 translated as a notational value.

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 Definition (directly nested):  A notational value is directly nested
 (within a literal value) if the innermost enclosing Value is a
 literal value.

7.1. Translation of Literal Values

 The translation of a literal value is either the attribute form
 translation of a literal value, or the element form translation of a
 literal value.
 The attribute form translation of a literal value is an attribute
 item with the [local name] "literalValue".  The [normalized value] of
 this attribute item is the RXER character data translation [RXER] of
 the literal value.
 The attribute form translation of a literal value SHALL NOT be used
 if:
 (1) the RXER Infoset translation of the literal value is not a
     character data translation [RXER] or is a character data
     translation that contains qualified names [XMLNS10][XMLNS11], or
 (2) attribute form translations of Value have been explicitly
     disallowed in the context where the literal value appears, or
 (3) the literal value has a nested notational value.
 The element form translation of a literal value is an element item
 with the [local name] "literalValue".  The [children] and
 [attributes] of the <literalValue> element item are set to the RXER
 Infoset translation of the literal value, except that a value of the
 EXTERNAL type (or a subtype thereof) is translated according to the
 associated type defined in Clause 34.5 of X.680 [X.680].  In
 addition, where the [children] and [attributes] of an element item in
 the translation correspond to a directly nested notational value, the
 translation specified in Section 7.2 MUST be used for the [children]
 and [attributes] of that element item, and an attribute item with the
 [local name] "literal", [namespace name]
 "urn:ietf:params:xml:ns:asnx", and [normalized value] "false" or "0"
 (i.e., asnx:literal="false") MUST be added to the [attributes] of
 that element item.
 Each outermost <literalValue> element item is required to be
 self-contained [RXER].
    Aside: An element item is self-contained if all namespace prefixes
    used by the element item and its contents are declared within the
    element item.

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    Aside: A <literalValue> element item nested within another
    <literalValue> element item is not required to be self-contained.
 An attribute item with the [local name] "literal", [namespace name]
 "urn:ietf:params:xml:ns:asnx" and [normalized value] "true" or "1"
 (i.e., asnx:literal="true") MAY be added to the [attributes] of the
 <literalValue> element item and/or any nested element item with
 content and attributes that correspond to a literal value.
    Aside: The asnx:literal attribute operates as a switch that
    indicates whether the content and other attributes of the element
    containing the attribute are interpreted as ASN.X notation (a
    notational value) or as an RXER encoding (a literal value).
 Example
    zero INTEGER ::= 0
    <namedValue name="zero" type="asnx:INTEGER" literalValue="0"/>
        OR
    <namedValue name="zero" type="asnx:INTEGER">
     <literalValue>0</literalValue>
    </namedValue>
 From the perspective of an ASN.X module as the RXER encoding of an
 ASN.1 value (an abstract value of the ModuleDefinition type in
 Appendix A), the type of the <literalValue> element is the
 unconstrained Markup type [RXER], not the governing type of the Value
 according to the ASN.1 specification.  This means that the Infoset
 representation of the <literalValue> element must be preserved in
 re-encodings of the ASN.X module.
 Similarly, the type of the literalValue attribute is a UTF8String,
 not the governing type of the Value according to the ASN.1
 specification.  This means that the exact characters of the
 [normalized value] of the attribute must be preserved in re-encodings
 of the ASN.X module.

7.2. Translation of Notational Values

 The translation of a notational value is the translation of the
 BuiltinValue, ReferencedValue, or ObjectClassFieldValue in the
 notational value.
 The translation of a ReferencedValue is the translation of the
 DefinedValue or ValueFromObject in the ReferencedValue.

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 The translation for each of these cases is described as creating an
 element item with the [local name] "value", which is appropriate for
 a notational value that stands on its own.  However, a notational
 value may also be directly nested within a literal value, in which
 case the [local name] will be determined according to RXER and the
 governing ASN.1 type of the enclosing literal value.
    Aside: In the latter case, the element item will also have a
    literal attribute item with the [normalized value] "false" or "0".
 A notational value that is not directly nested within a literal value
 MAY instead have the [local name] "literalValue" provided an
 attribute item with the [local name] "literal", [namespace name]
 "urn:ietf:params:xml:ns:asnx", and [normalized value] "false" or "0"
 is added to the [attributes] of the <literalValue> element item.
 Examples
    nothing INTEGER ::= zero
    <namedValue name="nothing" type="asnx:INTEGER" value="tns:zero"/>
        OR
    <namedValue name="nothing" type="asnx:INTEGER">
     <value ref="tns:zero"/><!-- A notational value. -->
    </namedValue>
        OR
    <namedValue name="nothing" type="asnx:INTEGER">
     <literalValue xmlns:asnx="urn:ietf:params:xml:ns:asnx"
                   xmlns:tns="http://example.com/ns/MyModule"
                   asnx:literal="false"
                   ref="tns:zero"/><!-- A notational value. -->
    </namedValue>
    integerList SEQUENCE OF number INTEGER ::= { zero, 3, 7 }
    <namedValue name="integerList">
     <type>
      <sequenceOf>
       <element name="number" type="asnx:INTEGER"/>
      </sequenceOf>
     </type>
     <literalValue xmlns:asnx="urn:ietf:params:xml:ns:asnx"
                   xmlns:tns="http://example.com/ns/MyModule">
      <number asnx:literal="false"

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              ref="tns:zero"/><!-- A notational value. -->
      <number>3</number><!-- A literal value. -->
      <number>7</number><!-- A literal value. -->
     </literalValue>
    </namedValue>

7.2.1. DefinedValue Translation

 If a DefinedValue is a valuereference (not a DummyReference) or an
 ExternalValueReference, then the translation of the DefinedValue is
 either the attribute form translation of a value reference, or the
 element form translation of a value reference.
 The attribute form translation of a value reference is an attribute
 item with the [local name] "value".  The [normalized value] of this
 attribute item is a qualified name for the expanded name of the
 referenced value definition (see Section 5.1).  The attribute form
 translation SHALL NOT be used if this expanded name is not distinct
 with respect to the current module and the modules referenced by its
 <import> element items (see Section 5.1).
 The element form translation of a value reference is an element item
 with the [local name] "value".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <value> element
 item.  An attribute item with the [local name] "ref" SHALL be added
 to the [attributes] of the <value> element item.  The
 [normalized value] of this attribute item is a qualified name for the
 expanded name of the referenced value definition.  If this expanded
 name is not distinct with respect to the current module and the
 modules referenced by its <import> element items, then an attribute
 item with the [local name] "context" SHALL be added to the
 [attributes] of the <value> element item; otherwise, if the module
 containing the referenced value definition has a schema identity URI,
 then an attribute item with the [local name] "context" MAY be added
 to the [attributes] of the <value> element item.  The
 [normalized value] of this attribute item is the schema identity URI
 of the module containing the value definition referenced by the
 DefinedValue.
    Aside: If a reference name is not distinct, then the module
    containing the referenced definition must have a schema identity
    URI (see Section 5.1).
 Usually the translator is free to choose either an attribute form or
 element form translation for a DefinedValue; however, in some
 contexts attribute forms of Value are explicitly disallowed.  In

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 particular, the attribute form translation SHALL NOT be used for a
 DefinedValue in a ReferencedValue in a Value that is directly nested
 in a literal value.
 If a DefinedValue is a DummyReference or ParameterizedValue, then the
 translation of the DefinedValue is the translation of that
 DummyReference or ParameterizedValue (see Section 13).

7.2.2. BuiltinValue Translation

 The translation of a BuiltinValue is the translation of the
 ChoiceValue, SequenceValue, SetValue, SequenceOfValue, SetOfValue, or
 TaggedValue in the BuiltinValue.
    Aside: There are other possibilities for a BuiltinValue, but these
    will all be literal values.  This section applies to a
    BuiltinValue that is a notational value.
 The translation of a TaggedValue is the translation of the Value in
 the TaggedValue (which is necessarily a notational value).
 The translation of a ChoiceValue is an element item with the
 [local name] "value".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <value> element
 item.  An element item with the same [local name] (i.e., "attribute",
 "element", "component", "group", or "member") as the translation of
 the NamedType corresponding to the identifier in the ChoiceValue
 SHALL be appended to the [children] of the <value> element item.  An
 attribute item with the [local name] "name" SHALL be added to the
 [attributes] of the <attribute>, <element>, <component>, <group>, or
 <member> element item.  The [normalized value] of this attribute item
 is a qualified name for the expanded name of the NamedType.  The
 translation of the Value in the ChoiceValue SHALL be added to the
 [children] or [attributes] of the <attribute>, <element>,
 <component>, <group>, or <member> element item.
 The translation of a SequenceValue or SetValue is an element item
 with the [local name] "value".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <value> element
 item.  If the SequenceValue or SetValue has a ComponentValueList,
 then the translation of each NamedValue nested in the
 ComponentValueList SHALL be appended to the [children] of the <value>
 element item in the order in which their corresponding NamedType
 instances appear in the definition of the governing type.

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 The translation of a SequenceOfValue or SetOfValue is an element item
 with the [local name] "value".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <value> element
 item.
 If the SequenceOfValue or SetOfValue has a NamedValueList, then the
 translation of each NamedValue nested in the NamedValueList SHALL be
 appended to the [children] of the <value> element item.
 If the SequenceOfValue or SetOfValue has a ValueList, then an element
 item with the same [local name] (i.e., "element" or "component") as
 the element item in the [children] of the <sequenceOf> or <setOf>
 element item in the translation of the governing type SHALL be
 appended to the [children] of the <value> element item for each Value
 nested in the ValueList.  An attribute item with the [local name]
 "name" and [normalized value] "item" SHALL be added to the
 [attributes] of the <element> or <component> element item.  The
 translation of the Value (from the ValueList) SHALL be added to the
 [children] or [attributes] of the <element> or <component> element
 item.
 The translation of a NamedValue is an element item with the same
 [local name] as the translation of the corresponding NamedType, i.e.,
 "attribute", "element", "component", "group", "item", or
 "simpleContent".  An attribute item with the [local name] "name"
 SHALL be added to the [attributes] of the element item.  The
 [normalized value] of this attribute item is a qualified name for the
 expanded name of the NamedType.  The translation of the Value in the
 NamedValue SHALL be added to the [children] or [attributes] of the
 element item.
 Examples
  1. - This is the governing type.

MyType ::= SEQUENCE {

         one    [ATTRIBUTE] INTEGER,
         two    INTEGER,
         three  [ATTRIBUTE][LIST] SEQUENCE OF number INTEGER
    }
    <namedType name="MyType">
     <type>
      <sequence>
       <attribute name="one" type="asnx:INTEGER"/>
       <element name="two" type="asnx:INTEGER"/>
       <attribute name="three">
        <type>
         <list>

Legg Experimental [Page 58] RFC 4912 Abstract Syntax Notation X July 2007

          <item name="number" type="asnx:INTEGER"/>
         </list>
        </type>
       </attribute>
      </sequence>
     </type>
    </namedType>
    myValue1 MyType ::= {
        one     456,
        two     123,
        three   { number 123, number 456 }
    }
    -- All literal values.
    <namedValue name="myValue1" type="tns:MyType">
     <literalValue one="456" three="123 456">
      <two>123</two>
     </literalValue>
    </namedValue>
    myValue2 MyType ::= {
        one     456,
        two     myObject.&number,
          -- only the value for component "two" is a notational value
        three   { number 123, number 456 }
    }
    <namedValue name="myValue2" type="tns:MyType">
     <literalValue xmlns:asnx="urn:ietf:params:xml:ns:asnx"
                   xmlns:tns="http://example.com/ns/MyModule"
                   one="456" three="123 456">
      <two asnx:literal="false">
       <fromObjects object="tns:myObject" fieldName="number"/>
      </two>
     </literalValue>
    </namedValue>
    myValue3 MyType ::= {
        one     myObject.&number,
        two     123,
        three   { number 123, number myObject.&number }
    }
    <namedValue name="myValue3" type="tns:MyType">
     <value>
      <attribute name="one">
       <value>

Legg Experimental [Page 59] RFC 4912 Abstract Syntax Notation X July 2007

        <fromObjects object="tns:myObject" fieldName="number"/>
       </value>
      </attribute>
      <element name="two" literalValue="123"/>
      <attribute name="three">
       <value>
        <item name="number" literalValue="123"/>
        <item name="number">
         <value>
          <fromObjects object="tns:myObject" fieldName="number"/>
         </value>
        </item>
       </value>
      </attribute>
     </value>
    </namedValue>

7.2.3. ValueFromObject Translation

 The translation of a ValueFromObject is an element item with the
 [local name] "value".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <value> element
 item.  An element item with the [local name] "fromObjects" SHALL be
 appended to the [children] of the <value> element item.
 The translation of the ReferencedObjects instance in the
 ValueFromObject SHALL be added to the [children] or [attributes] of
 the <fromObjects> element item.
 The translation of the FieldName in the ValueFromObject SHALL be
 added to the [children] or [attributes] of the <fromObjects> element
 item.

7.2.4. ObjectClassFieldValue Translation

 If an ObjectClassFieldValue is a BuiltinValue in a FixedTypeFieldVal,
 then the translation of the ObjectClassFieldValue is the translation
 of the BuiltinValue.
 If an ObjectClassFieldValue is a ReferencedValue in a
 FixedTypeFieldVal, then the translation of the ObjectClassFieldValue
 is the translation of the ReferencedValue.
 If an ObjectClassFieldValue is an OpenTypeFieldVal, then the
 translation of the ObjectClassFieldValue is an element item with the
 [local name] "value".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <value> element
 item.  An element item with the [local name] "openTypeValue" SHALL be

Legg Experimental [Page 60] RFC 4912 Abstract Syntax Notation X July 2007

 appended to the [children] of the <value> element item.  The
 translation of the Type in the OpenTypeFieldVal SHALL be added to the
 [children] or [attributes] of the <openTypeValue> element item.  The
 translation of the Value in the OpenTypeFieldVal SHALL be added to
 the [children] or [attributes] of the <openTypeValue> element item.
 Example
    myValue TYPE-IDENTIFIER.&Type ::= INTEGER:123
    <namedValue name="myValue">
     <type>
      <fromClass class="asnx:TYPE-IDENTIFIER" fieldName="Type"/>
     </type>
     <value>
      <openTypeValue type="asnx:INTEGER" literalValue="123"/>
     </value>
    </namedValue>

8. Translation of Value Sets

 The translation of a ValueSet is an element item with the
 [local name] "valueSet".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <valueSet> element
 item.  The translation of the ElementSetSpecs instance in the
 ValueSet SHALL be appended to the [children] of the <valueSet>
 element item.
 Example
    { 1 | 3..7, ..., 9..19 EXCEPT ( 11 | 12 ) }
    <valueSet>
     <union>
      <literalValue>1</literalValue>
      <range>
       <minInclusive literalValue="3"/>
       <maxInclusive literalValue="7"/>
      </range>
     </union>
     <extension>
      <all>
       <range>
        <minInclusive literalValue="9"/>
        <maxInclusive literalValue="19"/>
       </range>
       <except>
        <union>

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         <literalValue>11</literalValue>
         <literalValue>12</literalValue>
        </union>
       </except>
      </all>
     </extension>
    </valueSet>

8.1. ElementSetSpecs Translation

 The translation of an ElementSetSpecs instance where the ellipsis
 ("...") is not present is the translation of the ElementSetSpec in
 the RootElementSetSpec.
 The translation of an ElementSetSpecs instance where the ellipsis
 ("...") is present is the translation of the ElementSetSpec in the
 RootElementSetSpec followed by an element item with the [local name]
 "extension".  If an AdditionalElementSetSpec is present in the
 ElementSetSpecs, then the translation of the ElementSetSpec in the
 AdditionalElementSetSpec SHALL be added to the [children] of the
 <extension> element item.

8.2. ElementSetSpec Translation

 If an ElementSetSpec is of the "ALL Exclusions" form, then the
 translation of the ElementSetSpec is an element item with the
 [local name] "all".  An element item with the [local name] "except"
 SHALL be added to the [children] of the <all> element item.  The
 translation of the Elements instance in the Exclusions SHALL be added
 to the [children] of the <except> element item.
 If an ElementSetSpec is a Unions instance, then the translation of
 the ElementSetSpec is the translation of the Unions instance.
 If a Unions instance has only one nested Intersections instance, then
 the translation of the Unions instance is the translation of that
 Intersections instance; otherwise, the translation of the Unions
 instance is an element item with the [local name] "union".  In the
 latter case, the translation of each nested Intersections instance
 SHALL be appended to the [children] of the <union> element item.
 If an Intersections instance has only one nested IntersectionElements
 instance, then the translation of the Intersections instance is the
 translation of that IntersectionElements instance; otherwise, the
 translation of the Intersections instance is an element item with the
 [local name] "intersection".  In the latter case, the translation of
 each nested IntersectionElements instance SHALL be appended to the
 [children] of the <intersection> element item.

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 If an IntersectionElements instance is of the "Elems Exclusions"
 form, then the translation of the IntersectionElements instance is an
 element item with the [local name] "all".  The translation of the
 Elements instance in the Elems SHALL be added to the [children] of
 the <all> element item.  An element item with the [local name]
 "except" SHALL be appended to the [children] of the <all> element
 item.  The translation of the Elements instance in the Exclusions
 SHALL be added to the [children] of the <except> element item.
 If an IntersectionElements instance is an Elements instance, then the
 translation of the IntersectionElements instance is the translation
 of the Elements instance.
 The translation of an Elements instance is the translation of the
 SubtypeElements, ObjectSetElements, or ElementSetSpec in the Elements
 instance.

8.3. SubtypeElements Translation

 If a SubtypeElements instance is a SingleValue, then the translation
 of the SubtypeElements instance is the translation of the Value in
 the SingleValue, except that an attribute form of the Value
 translation SHALL NOT be used.
 If a SubtypeElements instance is a ContainedSubtype, then the
 translation of the SubtypeElements instance is an element item with
 the [local name] "includes".  The translation of the Type in the
 ContainedSubtype SHALL be added to the [children] or [attributes] of
 the <includes> element item.
 If a SubtypeElements instance is a ValueRange, then the translation
 of the SubtypeElements instance is the translation of the ValueRange.
 If a SubtypeElements instance is a SizeConstraint, then the
 translation of the SubtypeElements instance is an element item with
 the [local name] "size".  The translation of the Constraint in the
 SizeConstraint SHALL be added to the [children] of the <size> element
 item.
 If a SubtypeElements instance is a TypeConstraint, then the
 translation of the SubtypeElements instance is an element item with
 the [local name] "typeConstraint".  The translation of the Type in
 the TypeConstraint SHALL be added to the [children] or [attributes]
 of the <typeConstraint> element item.

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 If a SubtypeElements instance is a PermittedAlphabet, then the
 translation of the SubtypeElements instance is an element item with
 the [local name] "from".  The translation of the Constraint in the
 PermittedAlphabet SHALL be added to the [children] of the <from>
 element item.
 If a SubtypeElements instance is an InnerTypeConstraints instance,
 then the translation of the SubtypeElements instance is the
 translation of the InnerTypeConstraints instance.
 If a SubtypeElements instance is a PatternConstraint, then the
 translation of the SubtypeElements instance is an element item with
 the [local name] "pattern".  The translation of the Value in the
 PatternConstraint SHALL be added to the [children] or [attributes] of
 the <pattern> element item.

8.3.1. ValueRange Translation

 The translation of a ValueRange is an element item with the
 [local name] "range".
 If the LowerEndpoint in the ValueRange is of the "LowerEndValue <"
 form, then an element item with the [local name] "minExclusive" SHALL
 be added to the [children] of the <range> element item.  If the
 LowerEndValue is a Value, then the translation of the Value SHALL be
 added to the [children] or [attributes] of the <minExclusive> element
 item.
 If the LowerEndpoint in the ValueRange is of the "LowerEndValue" form
 and the LowerEndValue is a Value, then an element item with the
 [local name] "minInclusive" SHALL be added to the [children] of the
 <range> element item.  The translation of the Value in the
 LowerEndValue SHALL be added to the [children] or [attributes] of the
 <minInclusive> element item.
 If the LowerEndpoint in the ValueRange is of the "LowerEndValue" form
 and the LowerEndValue is "MIN", then an element item with the
 [local name] "minInclusive" MAY be added to the [children] of the
 <range> element item.
 If the UpperEndpoint in the ValueRange is of the "< UpperEndValue"
 form, then an element item with the [local name] "maxExclusive" SHALL
 be added to the [children] of the <range> element item.  If the
 UpperEndValue is a Value, then the translation of the Value SHALL be
 added to the [children] or [attributes] of the <maxExclusive> element
 item.

Legg Experimental [Page 64] RFC 4912 Abstract Syntax Notation X July 2007

 If the UpperEndpoint in the ValueRange is of the "UpperEndValue" form
 and the UpperEndValue is a Value, then an element item with the
 [local name] "maxInclusive" SHALL be added to the [children] of the
 <range> element item.  The translation of the Value in the
 UpperEndValue SHALL be added to the [children] or [attributes] of the
 <maxInclusive> element item.
 If the UpperEndpoint in the ValueRange is of the "UpperEndValue" form
 and the UpperEndValue is "MAX", then an element item with the
 [local name] "maxInclusive" MAY be added to the [children] of the
 <range> element item.
 Examples
    1..10
    <range>
     <minInclusive literalValue="1"/>
     <maxInclusive literalValue="10"/>
    </range>
    0..MAX
    <range>
     <minInclusive literalValue="0"/>
    </range>
    0<..<MAX
    <range>
     <minExclusive literalValue="0"/>
     <maxExclusive/>
    </range>

8.3.2. InnerTypeConstraints Translation

 The translation of an InnerTypeConstraints instance that has a
 SingleTypeConstraint is an element item with the [local name]
 "withComponent".  The translation of the Constraint in the
 SingleTypeConstraint SHALL be added to the [children] of the
 <withComponent> element item.
 The translation of an InnerTypeConstraints instance that has a
 MultipleTypeConstraints instance is an element item with the
 [local name] "withComponents".  If the MultipleTypeConstraints
 instance is a PartialSpecification, then an attribute item with the
 [local name] "partial" and the [normalized value] "true" or "1" SHALL
 be added to the [attributes] of the <withComponents> element item.

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 If the MultipleTypeConstraints instance is a FullSpecification, then
 an attribute item with the [local name] "partial" and the
 [normalized value] "false" or "0" MAY be added to the [attributes] of
 the <withComponents> element item.  The translation of each
 NamedConstraint nested in the TypeConstraints instance in the
 FullSpecification or PartialSpecification SHALL be appended to the
 [children] of the <withComponents> element item.
 The translation of a NamedConstraint is an element item with the same
 [local name] (i.e., "attribute", "element", "component", "group",
 "member", or "simpleContent") as the translation of the NamedType
 corresponding to the identifier in the NamedConstraint.  An attribute
 item with the [local name] "name" SHALL be added to the [attributes]
 of the <attribute>, <element>, <component>, <group>, <member>, or
 <simpleContent> element item.  The [normalized value] of this
 attribute item is a qualified name for the expanded name of the
 NamedType corresponding to the identifier in the NamedConstraint.
 If the PresenceConstraint in the ComponentConstraint in the
 NamedConstraint is not empty, then an attribute item with the
 [local name] "use" SHALL be added to the [attributes] of the
 <attribute>, <element>, <component>, <group>, <member>, or
 <simpleContent> element item.  The [normalized value] of this
 attribute item is the text of the PresenceConstraint with all letters
 downcased, i.e., either "present", "absent", or "optional".
 If the ValueConstraint in the ComponentConstraint in the
 NamedConstraint is not empty, then the translation of the Constraint
 in the ValueConstraint SHALL be added to the [children] of the
 <attribute>, <element>, <component>, <group>, <member>, or
 <simpleContent> element item.

9. Translation of Object Classes

 The translation of an ObjectClass is the translation of the
 DefinedObjectClass, ObjectClassDefn, or ParameterizedObjectClass in
 the ObjectClass.
 The translation of a ParameterizedObjectClass is described in
 Section 13.

9.1. DefinedObjectClass Translation

 If a DefinedObjectClass is an objectclassreference (not a
 DummyReference), an ExternalObjectClassReference, or a
 UsefulObjectClassReference, then the translation of the

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 DefinedObjectClass is either the attribute form translation of an
 object class reference, or the element form translation of an object
 class reference.
 The attribute form translation of an object class reference is an
 attribute item with the [local name] "class".  The [normalized value]
 of this attribute item is a qualified name for the expanded name of
 the referenced object class definition (see Section 5.1).  In the
 case of a UsefulObjectClassReference, the namespace name of the
 expanded name is "urn:ietf:params:xml:ns:asnx", and the local name is
 either "TYPE-IDENTIFIER" or "ABSTRACT-SYNTAX", as the case may be.
 The attribute form translation SHALL NOT be used if the expanded name
 is not distinct with respect to the current module and the modules
 referenced by its <import> element items (see Section 5.1).
 Otherwise, the translator is free to choose either the attribute form
 or element form translation for an object class reference.
 The element form translation of an object class reference is an
 element item with the [local name] "class".  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <class> element item.  An attribute item with the [local name] "ref"
 SHALL be added to the [attributes] of the <class> element item.  The
 [normalized value] of this attribute item is a qualified name for the
 expanded name of the referenced object class definition.  In the case
 of a UsefulObjectClassReference, the namespace name of the expanded
 name is "urn:ietf:params:xml:ns:asnx" and the local name is either
 "TYPE-IDENTIFIER" or "ABSTRACT-SYNTAX", as the case may be.  If the
 expanded name is not distinct with respect to the current module and
 the modules referenced by its <import> element items, then an
 attribute item with the [local name] "context" SHALL be added to the
 [attributes] of the <class> element item; otherwise, if the module
 containing the referenced object class definition has a schema
 identity URI, then an attribute item with the [local name] "context"
 MAY be added to the [attributes] of the <class> element item.  The
 [normalized value] of this attribute item is the schema identity URI
 of the module containing the referenced object class definition.
    Aside: If a reference name is not distinct, then the module
    containing the referenced definition must have a schema identity
    URI (see Section 5.1).
 The translation of the DefinedObjectClass is the same whether the
 object class definition is referenced by an objectclassreference or
 an ExternalObjectClassReference.
 If a DefinedObjectClass is a DummyReference, then the translation of
 the DefinedObjectClass is the translation of the DummyReference (see
 Section 13).

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9.2. ObjectClassDefn Translation

 The translation of an ObjectClassDefn is an element item with the
 [local name] "class".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <class> element
 item.  The translation of each FieldSpec in the ObjectClassDefn SHALL
 be appended to the [children] of the <class> element item.
 The translation of a FieldSpec is the translation of the
 TypeFieldSpec, FixedTypeValueFieldSpec, VariableTypeValueFieldSpec,
 FixedTypeValueSetFieldSpec, VariableTypeValueSetFieldSpec,
 ObjectFieldSpec, or ObjectSetFieldSpec in the FieldSpec.

9.2.1. TypeFieldSpec Translation

 The translation of a TypeFieldSpec where the TypeOptionalitySpec is
 absent is an element item with the [local name] "typeField".
 The translation of a TypeFieldSpec with a TypeOptionalitySpec of the
 "OPTIONAL" form is an element item with the [local name] "optional".
 An element item with the [local name] "typeField" SHALL be added to
 the [children] of the <optional> element item.
 The translation of a TypeFieldSpec with a TypeOptionalitySpec of the
 "DEFAULT Type" form is an element item with the [local name]
 "optional".  An element item with the [local name] "typeField" SHALL
 be added to the [children] of the <optional> element item.  An
 element item with the [local name] "default" SHALL be appended to the
 [children] of the <optional> element item.  The translation of the
 Type in the TypeOptionalitySpec SHALL be added to the [children] or
 [attributes] of the <default> element item.
 An attribute item with the [local name] "name" SHALL be added to the
 [attributes] of the <typeField> element item.  The [normalized value]
 of this attribute item is the typefieldreference in the
 TypeFieldSpec, without the ampersand character ('&', U+0026).  An
 element item with the [local name] "annotation" MAY be added to the
 [children] of the <typeField> element item.
 Example
    CLASS {
        &One,
        &Two    OPTIONAL,
        &Three  DEFAULT OBJECT IDENTIFIER
    }

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    <class>
     <typeField name="One"/>
     <optional>
      <typeField name="Two"/>
     </optional>
     <optional>
      <typeField name="Three"/>
      <default type="asnx:OBJECT-IDENTIFIER"/>
     </optional>
    </class>

9.2.2. FixedTypeValueFieldSpec Translation

 The translation of a FixedTypeValueFieldSpec where the
 ValueOptionalitySpec is absent is an element item with the
 [local name] "valueField".
 The translation of a FixedTypeValueFieldSpec with a
 ValueOptionalitySpec of the "OPTIONAL" form is an element item with
 the [local name] "optional".  An element item with the [local name]
 "valueField" SHALL be added to the [children] of the <optional>
 element item.
 The translation of a FixedTypeValueFieldSpec with a
 ValueOptionalitySpec of the "DEFAULT Value" form is an element item
 with the [local name] "optional".  An element item with the
 [local name] "valueField" SHALL be added to the [children] of the
 <optional> element item.  An element item with the [local name]
 "default" SHALL be appended to the [children] of the <optional>
 element item.  The translation of the Value in the
 ValueOptionalitySpec SHALL be added to the [children] or [attributes]
 of the <default> element item.
 An attribute item with the [local name] "name" SHALL be added to the
 [attributes] of the <valueField> element item.  The
 [normalized value] of this attribute item is the valuefieldreference
 in the FixedTypeValueFieldSpec, without the ampersand character ('&',
 U+0026).  If the "UNIQUE" keyword is present, then an attribute item
 with the [local name] "unique" and [normalized value] "true" or "1"
 SHALL be added to the [attributes] of the <valueField> element item;
 otherwise, an attribute item with the [local name] "unique" and
 [normalized value] "false" or "0" MAY be added to the [attributes] of
 the <valueField> element item.  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <valueField>
 element item.  The translation of the Type in the
 FixedTypeValueFieldSpec SHALL be added to the [children] or
 [attributes] of the <valueField> element item.

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 Example
    CLASS {
        &one    OBJECT IDENTIFIER UNIQUE,
        &two    BOOLEAN OPTIONAL,
        &three  INTEGER DEFAULT 0
    }
    <class>
     <valueField name="one" unique="true"
                 type="asnx:OBJECT-IDENTIFIER"/>
     <optional>
      <valueField name="two" type="asnx:BOOLEAN"/>
     </optional>
     <optional>
      <valueField name="three" type="asnx:INTEGER"/>
      <default literalValue="0"/>
     </optional>
    </class>

9.2.3. FixedTypeValueSetFieldSpec Translation

 The translation of a FixedTypeValueSetFieldSpec where the
 ValueSetOptionalitySpec is absent is an element item with the
 [local name] "valueSetField".
 The translation of a FixedTypeValueSetFieldSpec with a
 ValueSetOptionalitySpec of the "OPTIONAL" form is an element item
 with the [local name] "optional".  An element item with the
 [local name] "valueSetField" SHALL be added to the [children] of the
 <optional> element item.
 The translation of a FixedTypeValueSetFieldSpec with a
 ValueSetOptionalitySpec of the "DEFAULT ValueSet" form is an element
 item with the [local name] "optional".  An element item with the
 [local name] "valueSetField" SHALL be added to the [children] of the
 <optional> element item.  An element item with the [local name]
 "default" SHALL be appended to the [children] of the <optional>
 element item.  The translation of the ValueSet in the
 ValueSetOptionalitySpec SHALL be added to the [children] of the
 <default> element item.
 An attribute item with the [local name] "name" SHALL be added to the
 [attributes] of the <valueSetField> element item.  The
 [normalized value] of this attribute item is the
 valuesetfieldreference in the FixedTypeValueSetFieldSpec, without the
 ampersand character ('&', U+0026).  An element item with the
 [local name] "annotation" MAY be added to the [children] of the

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 <valueSetField> element item.  The translation of the Type in the
 FixedTypeValueSetFieldSpec SHALL be added to the [children] or
 [attributes] of the <valueSetField> element item.
 Example
    CLASS {
        &One    UTF8String,
        &Two    BOOLEAN OPTIONAL,
        &Three  INTEGER DEFAULT { 1 | 2 }
    }
    <class>
     <valueSetField name="One" type="asnx:UTF8String"/>
     <optional>
      <valueSetField name="Two" type="asnx:BOOLEAN"/>
     </optional>
     <optional>
      <valueSetField name="Three" type="asnx:INTEGER"/>
      <default>
       <valueSet>
        <union>
         <literalValue>1</literalValue>
         <literalValue>2</literalValue>
        </union>
       </valueSet>
      </default>
     </optional>
    </class>

9.2.4. VariableTypeValueFieldSpec Translation

 The translation of a VariableTypeValueFieldSpec where the
 ValueOptionalitySpec is absent is an element item with the
 [local name] "valueField".
 The translation of a VariableTypeValueFieldSpec with a
 ValueOptionalitySpec of the "OPTIONAL" form is an element item with
 the [local name] "optional".  An element item with the [local name]
 "valueField" SHALL be added to the [children] of the <optional>
 element item.
 The translation of a VariableTypeValueFieldSpec with a
 ValueOptionalitySpec of the "DEFAULT Value" form is an element item
 with the [local name] "optional".  An element item with the
 [local name] "valueField" SHALL be added to the [children] of the
 <optional> element item.  An element item with the [local name]
 "default" SHALL be appended to the [children] of the <optional>

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 element item.  The translation of the Value in the
 ValueOptionalitySpec SHALL be added to the [children] or [attributes]
 of the <default> element item.
 An attribute item with the [local name] "name" SHALL be added to the
 [attributes] of the <valueField> element item.  The
 [normalized value] of this attribute item is the valuefieldreference
 in the VariableTypeValueFieldSpec, without the ampersand character
 ('&', U+0026).  An element item with the [local name] "annotation"
 MAY be added to the [children] of the <valueField> element item.  An
 element item with the [local name] "typeFromField" SHALL be appended
 to the [children] of the <valueField> element item.  The translation
 of the FieldName in the VariableTypeValueFieldSpec SHALL be added to
 the [children] or [attributes] of the <typeFromField> element item.
 Example
    CLASS {
        &Syntax DEFAULT INTEGER,
        &one    &Syntax,
        &two    &Syntax OPTIONAL,
        &three  &Syntax DEFAULT 0
    }
    <class>
     <optional>
      <typeField name="Syntax"/>
      <default type="asnx:INTEGER"/>
     </optional>
     <valueField name="one">
      <typeFromField fieldName="Syntax"/>
     </valueField>
     <optional>
      <valueField name="two">
       <typeFromField fieldName="Syntax"/>
      </valueField>
     </optional>
     <optional>
      <valueField name="three">
       <typeFromField fieldName="Syntax"/>
      </valueField>
      <default literalValue="0"/>
     </optional>
    </class>

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9.2.5. VariableTypeValueSetFieldSpec Translation

 The translation of a VariableTypeValueSetFieldSpec where the
 ValueSetOptionalitySpec is absent is an element item with the
 [local name] "valueSetField".
 The translation of a VariableTypeValueSetFieldSpec with a
 ValueSetOptionalitySpec of the "OPTIONAL" form is an element item
 with the [local name] "optional".  An element item with the
 [local name] "valueSetField" SHALL be added to the [children] of the
 <optional> element item.
 The translation of a VariableTypeValueSetFieldSpec with a
 ValueSetOptionalitySpec of the "DEFAULT ValueSet" form is an element
 item with the [local name] "optional".  An element item with the
 [local name] "valueSetField" SHALL be added to the [children] of the
 <optional> element item.  An element item with the [local name]
 "default" SHALL be appended to the [children] of the <optional>
 element item.  The translation of the ValueSet in the
 ValueSetOptionalitySpec SHALL be added to the [children] of the
 <default> element item.
 An attribute item with the [local name] "name" SHALL be added to the
 [attributes] of the <valueSetField> element item.  The
 [normalized value] of this attribute item is the
 valuesetfieldreference in the VariableTypeValueSetFieldSpec, without
 the ampersand character ('&', U+0026).  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <valueSetField> element item.  An element item with the [local name]
 "typeFromField" SHALL be appended to the [children] of the
 <valueSetField> element item.  The translation of the FieldName in
 the VariableTypeValueSetFieldSpec SHALL be added to the [children] or
 [attributes] of the <typeFromField> element item.
 Example
    CLASS {
        &Syntax DEFAULT INTEGER,
        &One    &Syntax,
        &Two    &Syntax OPTIONAL,
        &Three  &Syntax DEFAULT { 1 | 2 }
    }
    <class>
     <optional>
      <typeField name="Syntax"/>
      <default type="asnx:INTEGER"/>
     </optional>

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     <valueSetField name="One">
      <typeFromField fieldName="Syntax"/>
     </valueSetField>
     <optional>
      <valueSetField name="Two">
       <typeFromField fieldName="Syntax"/>
      </valueSetField>
     </optional>
     <optional>
      <valueSetField name="Three">
       <typeFromField fieldName="Syntax"/>
      </valueSetField>
      <default>
       <valueSet>
        <union>
         <literalValue>1</literalValue>
         <literalValue>2</literalValue>
        </union>
       </valueSet>
      </default>
     </optional>
    </class>

9.2.6. FieldName Translation

 The translation of a FieldName is either, at the translator's option,
 an attribute item with the [local name] "fieldName" added to the
 [attributes] of the enclosing element item, or an element item with
 the [local name] "fieldName" appended to the [children] of the
 enclosing element item.
 The [normalized value] of the fieldName attribute item is a solidus
 ('/', U+002F) separated list of the PrimitiveFieldName instances in
 the FieldName, without the ampersand characters ('&', U+0026).
 Leading and/or trailing white space characters MAY be added to the
 [normalized value] of the attribute item.  White space characters MAY
 be added immediately before and/or after any solidus character ('/',
 U+002F) in the [normalized value].
 The [children] property of the <fieldName> element item is set to the
 sequence of character items for a solidus ('/', U+002F) separated
 list of the PrimitiveFieldName instances in the FieldName, without
 the ampersand characters ('&', U+0026).  Leading and/or trailing
 white space character items MAY be added to the [children] of the
 <fieldName> element item.  White space character items MAY be added
 immediately before and/or after any character item for the solidus
 character ('/', U+002F).

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 Example
    &Linked.&ArgumentType
    <fieldName>Linked/ArgumentType</fieldName>

9.2.7. ObjectFieldSpec Translation

 The translation of an ObjectFieldSpec where the ObjectOptionalitySpec
 is absent is an element item with the [local name] "objectField".
 The translation of an ObjectFieldSpec with an ObjectOptionalitySpec
 of the "OPTIONAL" form is an element item with the [local name]
 "optional".  An element item with the [local name] "objectField"
 SHALL be added to the [children] of the <optional> element item.
 The translation of an ObjectFieldSpec with an ObjectOptionalitySpec
 of the "DEFAULT Object" form is an element item with the [local name]
 "optional".  An element item with the [local name] "objectField"
 SHALL be added to the [children] of the <optional> element item.  An
 element item with the [local name] "default" SHALL be appended to the
 [children] of the <optional> element item.  The translation of the
 Object in the ObjectOptionalitySpec SHALL be added to the [children]
 or [attributes] of the <default> element item.
 An attribute item with the [local name] "name" SHALL be added to the
 [attributes] of the <objectField> element item.  The
 [normalized value] of this attribute item is the objectfieldreference
 in the ObjectFieldSpec, without the ampersand character ('&',
 U+0026).  An element item with the [local name] "annotation" MAY be
 added to the [children] of the <objectField> element item.  The
 translation of the DefinedObjectClass in the ObjectFieldSpec SHALL be
 added to the [children] or [attributes] of the <objectField> element
 item.
 Example
    CLASS {
        &one    TYPE-IDENTIFIER,
        &two    ABSTRACT-SYNTAX OPTIONAL,
        &three  TYPE-IDENTIFIER DEFAULT myObject
    }

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    <class>
     <objectField name="one" class="asnx:TYPE-IDENTIFIER"/>
     <optional>
      <objectField name="two" class="asnx:ABSTRACT-SYNTAX"/>
     </optional>
     <optional>
      <objectField name="three" class="asnx:TYPE-IDENTIFIER"/>
      <default object="tns:myObject"/>
     </optional>
    </class>

9.2.8. ObjectSetFieldSpec Translation

 The translation of an ObjectSetFieldSpec where the
 ObjectSetOptionalitySpec is absent is an element item with the
 [local name] "objectSetField".
 The translation of an ObjectSetFieldSpec with an
 ObjectSetOptionalitySpec of the "OPTIONAL" form is an element item
 with the [local name] "optional".  An element item with the
 [local name] "objectSetField" SHALL be added to the [children] of the
 <optional> element item.
 The translation of an ObjectSetFieldSpec with an
 ObjectSetOptionalitySpec of the "DEFAULT ObjectSet" form is an
 element item with the [local name] "optional".  An element item with
 the [local name] "objectSetField" SHALL be added to the [children] of
 the <optional> element item.  An element item with the [local name]
 "default" SHALL be appended to the [children] of the <optional>
 element item.  The translation of the ObjectSet in the
 ObjectSetOptionalitySpec SHALL be added to the [children] or
 [attributes] of the <default> element item.
 An attribute item with the [local name] "name" SHALL be added to the
 [attributes] of the <objectSetField> element item.  The
 [normalized value] of this attribute item is the
 objectsetfieldreference in the ObjectSetFieldSpec, without the
 ampersand character ('&', U+0026).  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <objectSetField> element item.  The translation of the
 DefinedObjectClass in the ObjectSetFieldSpec SHALL be added to the
 [children] or [attributes] of the <objectSetField> element item.

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 Example
    CLASS {
        &One    TYPE-IDENTIFIER,
        &Two    ABSTRACT-SYNTAX OPTIONAL,
        &Three  TYPE-IDENTIFIER DEFAULT { myObject }
    }
    <class>
     <objectSetField name="One" class="asnx:TYPE-IDENTIFIER"/>
     <optional>
      <objectSetField name="Two" class="asnx:ABSTRACT-SYNTAX"/>
     </optional>
     <optional>
      <objectSetField name="Three" class="asnx:TYPE-IDENTIFIER"/>
      <default>
       <objectSet>
        <object ref="tns:myObject"/>
       </objectSet>
      </default>
     </optional>
    </class>

10. Translation of Objects

 The translation of an Object is the translation of the DefinedObject,
 ObjectDefn, ObjectFromObject, or ParameterizedObject in the Object.
 The translation of a ParameterizedObject is described in Section 13.

10.1. DefinedObject Translation

 If a DefinedObject is an objectreference (not a DummyReference) or an
 ExternalObjectReference, then the translation of the DefinedObject is
 either the attribute form translation of an object reference, or the
 element form translation of an object reference.
 The attribute form translation of an object reference is an attribute
 item with the [local name] "object".  The [normalized value] of this
 attribute item is a qualified name for the expanded name of the
 referenced object definition (see Section 5.1).  The attribute form
 translation SHALL NOT be used if this expanded name is not distinct
 with respect to the current module and the modules referenced by its
 <import> element items (see Section 5.1).
 The element form translation of an object reference is an element
 item with the [local name] "object".  An element item with the
 [local name] "annotation" MAY be added to the [children] of the

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 <object> element item.  An attribute item with the [local name] "ref"
 SHALL be added to the [attributes] of the <object> element item.  The
 [normalized value] of this attribute item is a qualified name for the
 expanded name of the referenced object definition.  If this expanded
 name is not distinct with respect to the current module and the
 modules referenced by its <import> element items, then an attribute
 item with the [local name] "context" SHALL be added to the
 [attributes] of the <object> element item; otherwise, if the module
 containing the referenced object definition has a schema identity
 URI, then an attribute item with the [local name] "context" MAY be
 added to the [attributes] of the <object> element item.  The
 [normalized value] of this attribute item is the schema identity URI
 of the module containing the referenced object definition.
    Aside: If a reference name is not distinct, then the module
    containing the referenced definition must have a schema identity
    URI (see Section 5.1).
 The translation of the DefinedObject is the same whether the object
 definition is referenced by an objectreference or an
 ExternalObjectReference.
 Usually the translator is free to choose either the attribute form or
 element form translation for an object reference; however, in some
 contexts the attribute form is explicitly disallowed.
 If a DefinedObject is a DummyReference, then the translation of the
 DefinedObject is the translation of the DummyReference (see
 Section 13).

10.2. ObjectDefn Translation

 An ObjectDefn that is a DefinedSyntax is first converted to the
 equivalent DefaultSyntax and then translated.
 The translation of an ObjectDefn is an element item with the
 [local name] "object".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <object> element
 item.  The translation of each FieldSetting in the DefaultSyntax in
 the ObjectClassDefn SHALL be appended to the [children] of the
 <object> element item.
 The translation of a FieldSetting is an element item with the
 [local name] "field".  An attribute item with the [local name] "name"
 SHALL be added to the [attributes] of the <field> element item.  The
 [normalized value] of this attribute item is the PrimitiveFieldName
 in the FieldSetting, without the ampersand character ('&', U+0026).
 The translation of the Type, Value, ValueSet, Object, or ObjectSet in

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 the Setting in the FieldSetting SHALL be added to the [children] or
 [attributes] of the <field> element item.
 Example
  1. - This is the governing object class.

ONE-OF-EVERYTHING ::= CLASS {

        &One,
        &two    INTEGER,
        &Three  INTEGER,
        &four   TYPE-IDENTIFIER,
        &Five   TYPE-IDENTIFIER
    }
    <namedClass name="ONE-OF-EVERYTHING">
     <class>
      <typeField name="One"/>
      <valueField name="two" type="asnx:INTEGER"/>
      <valueSetField name="Three" type="asnx:INTEGER"/>
      <objectField name="four" class="asnx:TYPE-IDENTIFIER"/>
      <objectSetField name="Five" class="asnx:TYPE-IDENTIFIER"/>
     </class>
    </namedClass>
    mixedBag ONE-OF-EVERYTHING ::= {
        &One    BOOLEAN,
        &two    99,
        &Three  { 1 | 2 },
        &four   myObject,
        &Five   { myObject }
    }
    <namedObject name="mixedBag" class="tns:ONE-OF-EVERYTHING">
     <object>
      <field name="One" type="asnx:BOOLEAN"/>
      <field name="two" literalValue="99"/>
      <field name="Three">
       <valueSet>
        <union>
         <literalValue>1</literalValue>
         <literalValue>2</literalValue>
        </union>
       </valueSet>
      </field>
      <field name="four" object="tns:myObject"/>
      <field name="Five">
       <objectSet>
        <object ref="tns:myObject"/>

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       </objectSet>
      </field>
     </object>
    </namedObject>

10.3. ObjectFromObject Translation

 The translation of an ObjectFromObject is an element item with the
 [local name] "object".  An element item with the [local name]
 "annotation" MAY be added to the [children] of the <object> element
 item.  An element item with the [local name] "fromObjects" SHALL be
 appended to the [children] of the <object> element item.
 The translation of the ReferencedObjects instance in the
 ObjectFromObject SHALL be added to the [children] or [attributes] of
 the <fromObjects> element item.
 The translation of the FieldName in the ObjectFromObject SHALL be
 added to the [children] or [attributes] of the <fromObjects> element
 item.

11. Translation of Object Sets

 If an ObjectSet matches the form "{ DefinedObjectSet }" (i.e., a
 DefinedObjectSet in an ObjectSetElements instance in an Elements
 instance in a lone IntersectionElements instance in a lone
 Intersections instance in a Unions instance in an ElementSetSpec in a
 RootElementSetSpec in an ObjectSetSpec without an
 AdditionalElementSetSpec), then the translator MAY use the
 translation of the DefinedObjectSet as the translation of the
 ObjectSet; otherwise, the translation of an ObjectSet is an element
 item with the [local name] "objectSet".  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <objectSet> element item.  The translation of the ObjectSetSpec in
 the ObjectSet SHALL be appended to the [children] of the <objectSet>
 element item.
    Aside: An ObjectSet that is directly a DefinedObjectSet is a
    notational capability that does not exist in ASN.1, but is allowed
    in ASN.X to avoid excessive nesting of <objectSet> element items
    in the expansion of parameterized definitions.
 If an ObjectSetSpec contains only a RootElementSetSpec, then the
 translation of the ObjectSetSpec is the translation of the
 ElementSetSpec in the RootElementSetSpec.

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 If an ObjectSetSpec contains a RootElementSetSpec and an ellipsis
 ("..."), then the translation of the ObjectSetSpec is the translation
 of the ElementSetSpec in the RootElementSetSpec followed by an
 element item with the [local name] "extension".  If an
 AdditionalElementSetSpec is present, then the translation of the
 ElementSetSpec in the AdditionalElementSetSpec SHALL be added to the
 [children] of the <extension> element item.
 If an ObjectSetSpec does not contain a RootElementSetSpec, then the
 translation of the ObjectSetSpec is an element item with the
 [local name] "extension".  If an AdditionalElementSetSpec is present,
 then the translation of the ElementSetSpec in the
 AdditionalElementSetSpec SHALL be added to the [children] of the
 <extension> element item.
 Nested within the ElementSetSpec will be one or more
 ObjectSetElements instances.

11.1. DefinedObjectSet Translation

 If a DefinedObjectSet is an objectsetreference (not a DummyReference)
 or an ExternalObjectSetReference, then the translation of the
 DefinedObjectSet is either the attribute form translation of an
 object set reference, or the element form translation of an object
 set reference.
 The attribute form translation of an object set reference is an
 attribute item with the [local name] "objectSet".  The
 [normalized value] of this attribute item is a qualified name for the
 expanded name of the referenced object set definition (see
 Section 5.1).  The attribute form translation SHALL NOT be used if
 this expanded name is not distinct with respect to the current module
 and the modules referenced by its <import> element items (see
 Section 5.1).
 The element form translation of an object set reference is an element
 item with the [local name] "objectSet".  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <objectSet> element item.  An attribute item with the [local name]
 "ref" SHALL be added to the [attributes] of the <objectSet> element
 item.  The [normalized value] of this attribute item is a qualified
 name for the expanded name of the referenced object set definition.
 If this expanded name is not distinct with respect to the current
 module and the modules referenced by its <import> element items, then
 an attribute item with the [local name] "context" SHALL be added to
 the [attributes] of the <objectSet> element item; otherwise, if the
 module containing the referenced object set definition has a schema
 identity URI, then an attribute item with the [local name] "context"

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 MAY be added to the [attributes] of the <objectSet> element item.
 The [normalized value] of this attribute item is the schema identity
 URI of the module containing the referenced object set definition.
    Aside: If a reference name is not distinct, then the module
    containing the referenced definition must have a schema identity
    URI (see Section 5.1).
 The translation of the DefinedObjectSet is the same whether the
 object definition is referenced by an objectsetreference or an
 ExternalObjectSetReference.
 Usually the translator is free to choose either the attribute form or
 element form translation for an object set reference; however, in
 some contexts the attribute form is explicitly disallowed.
 If a DefinedObjectSet is a DummyReference, then the translation of
 the DefinedObjectSet is the translation of the DummyReference (see
 Section 13).

11.2. ObjectSetElements Translation

 If an ObjectSetElements instance is an Object, then the translation
 of the ObjectSetElements instance is the translation of the Object,
 except that the attribute form of the DefinedObject translation SHALL
 NOT be used if the Object is a DefinedObject.
 If an ObjectSetElements instance is a DefinedObjectSet, then the
 translation of the ObjectSetElements instance is the translation of
 the DefinedObjectSet, except that the attribute form of the
 DefinedObjectSet translation SHALL NOT be used.
 If an ObjectSetElements instance is an ObjectSetFromObjects, then the
 translation of the ObjectSetElements instance is the translation of
 the ObjectSetFromObjects.
 If an ObjectSetElements instance is a ParameterizedObjectSet, then
 the translation of the ObjectSetElements instance is the translation
 of the ParameterizedObjectSet (see Section 13).
    Aside: The in-line expansion of a ParameterizedObjectSet results
    in an ObjectSet.  An ObjectSetElements instance that is an
    ObjectSet is a notational capability that does not exist in ASN.1,
    but is allowed in ASN.X to avoid the need to manufacture a
    reference name for the expanded parameterized definition.

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11.2.1. ObjectSetFromObjects Translation

 The translation of an ObjectSetFromObjects instance is an element
 item with the [local name] "objectSet".  An element item with the
 [local name] "annotation" MAY be added to the [children] of the
 <objectSet> element item.  An element item with the [local name]
 "fromObjects" SHALL be appended to the [children] of the <objectSet>
 element item.
 The translation of the ReferencedObjects instance in the
 ObjectSetFromObjects SHALL be added to the [children] or [attributes]
 of the <fromObjects> element item.
 The translation of the FieldName in the ObjectSetFromObjects SHALL be
 added to the [children] or [attributes] of the <fromObjects> element
 item.

12. Translation of Information From Objects

 If a ReferencedObjects instance is a DefinedObject (not a
 DummyReference), then the translation of the ReferencedObjects
 instance is the translation of the DefinedObject.
 If a ReferencedObjects instance is a DefinedObjectSet (not a
 DummyReference), then the translation of the ReferencedObjects
 instance is the translation of the DefinedObjectSet.
 If a ReferencedObjects instance is a DummyReference,
 ParameterizedObject, or ParameterizedObjectSet, then the translation
 of the ReferencedObjects instance is the translation of that
 DummyReference, ParameterizedObject, or ParameterizedObjectSet (see
 Section 13).
    Aside: The in-line expansion of a ParameterizedObject or
    ParameterizedObjectSet results in an Object or ObjectSet,
    respectively.  A ReferencedObjects instance that is an Object or
    ObjectSet is a notational capability that does not exist in ASN.1,
    but is allowed in ASN.X to avoid the need to manufacture a
    reference name for an expanded parameterized definition.

13. Translation of Parameterized Definitions

 The translation of an ASN.1 specification into ASN.X replaces any
 DummyReference [X.683] or reference to a parameterized definition
 [X.683] with the definition expanded in-line (except for a special
 case involving recursive parameterized types).  For example, a
 ParameterizedObject is replaced by the Object on the right-hand side
 of the referenced ParameterizedObjectAssignment.

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 The definition that substitutes for a DummyReference or parameterized
 reference (e.g., the Object that substitutes for a
 ParameterizedObject) potentially comes from a different module from
 the reference.  Expanding a DummyReference or parameterized reference
 in-line puts the substitute definition into the context of the module
 containing the reference, which could therefore alter the
 interpretation of the substitute definition.
 A type definition is potentially dependent on the TagDefault and
 ExtensionDefault of the module in which it appears, and may also be
 affected by encoding instructions in an XML Encoding Rules (XER)
 [X.693] encoding control section [X.693-1].  Other kinds of
 definitions are not dependent on the module context; however, type
 definitions can be nested within the other kinds of definitions, so a
 change of context can still be significant.
    Aside: Type definitions are not dependent on their module's RXER
    or Generic String Encoding Rules (GSER) [GSER] encoding control
    section [RXEREI][GSEREI] (as they are currently defined), so the
    presence of an encoding control section for RXER or GSER is not
    significant in a change of context.
 The remainder of this section describes how and when a change of
 context is indicated in the ASN.X translation of a DummyReference or
 parameterized reference.
 In any instance of use, the module containing the DummyReference or
 parameterized reference is the referencing module, and the module
 providing the substitute definition is the referenced module.  The
 referenced and referencing modules may be the same module.
 In the case of a ParameterizedType, the substitute definition is the
 Type on the right-hand side of the referenced
 ParameterizedTypeAssignment.
 In the case of a ParameterizedValueSetType, the substitute definition
 is the constrained type on the right-hand side of the notional
 ParameterizedTypeAssignment equivalent to the referenced
 ParameterizedValueSetTypeAssignment (see Clause 15.8 of X.680
 [X.680]).
 In the case of a ParameterizedValue, the substitute definition is the
 Value on the right-hand side of the referenced
 ParameterizedValueAssignment.
 In the case of a ParameterizedObjectClass, the substitute definition
 is the ObjectClass on the right-hand side of the referenced
 ParameterizedObjectClassAssignment.

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 In the case of a ParameterizedObject, the substitute definition is
 the Object on the right-hand side of the referenced
 ParameterizedObjectAssignment.
 In the case of a ParameterizedObjectSet, the substitute definition is
 the ObjectSet on the right-hand side of the referenced
 ParameterizedObjectSetAssignment.
 If the ActualParameter corresponding to a DummyReference is not a
 ValueSet, then the substitute definition for that DummyReference is
 the Type, Value, DefinedObjectClass, Object, or ObjectSet in the
 ActualParameter.
 If the ActualParameter corresponding to a DummyReference is a
 ValueSet, then the substitute definition for that DummyReference is
 the notional constrained type equivalent to the ValueSet; the
 ElementSetSpecs of the ValueSet contributes to the constraint of the
 constrained type, and the governor of the Parameter corresponding to
 the ActualParameter is used as the parent type that is constrained.
 Definition (interchangeable):  The contexts of the referencing and
 referenced modules are interchangeable with respect to interpreting
 the substitute definition if:
 (1) the referenced module is the referencing module and does not
     contain an XER encoding control section, or
 (2) the referenced module and referencing module have the same
     TagDefault (where an absent TagDefault is taken to be equivalent
     to "EXPLICIT TAGS"), the referenced module and referencing module
     have the same ExtensionDefault, and neither module has an XER
     encoding control section.
    Aside: A module with an XER encoding control section is not
    considered to have a context interchangeable with another module,
    including itself, because the typereference by which a substitute
    type definition is identified may appear in a TargetList in the
    XER encoding control section of the referenced module, and because
    the in-line expansion of a substitute definition may cause its
    text to come within the scope of a TargetList in the XER encoding
    control section of the referencing module that would not apply
    otherwise.
 Definition (recursively contained):  A ParameterizedType is
 recursively contained if its translation will be nested within the
 translation (i.e., in-line expansion) of another ParameterizedType to

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 which it is equivalent.  A ParameterizedValueSetType is recursively
 contained if its translation will be nested within the translation of
 another ParameterizedValueSetType to which it is equivalent.
    Aside: ASN.1 does not permit the other kinds of parameterized
    reference to be recursive.
 The translation of a DummyReference, a ParameterizedType that is not
 recursively contained, a ParameterizedValue, a
 ParameterizedValueSetType that is not recursively contained, a
 ParameterizedObjectClass, a ParameterizedObject, or a
 ParameterizedObjectSet is either:
 (a) the translation of the substitute definition, or
 (b) an element item with the [local name] "type" if the substitute
     definition is a Type, "value" if the substitute definition is a
     Value, "class" if the substitute definition is an ObjectClass or
     DefinedObjectClass, "object" if the substitute definition is an
     Object, or "objectSet" if the substitute definition is an
     ObjectSet.  A fully expanded reference (described shortly) SHALL
     be added to the [children] of the element item.
 The translation in case (b) is always allowed and provides
 information to identify the referenced module and the referenced
 definition.
 The translation in case (a) MAY be used instead if and only if the
 contexts of the referencing and referenced modules are
 interchangeable, or the contexts of the referencing and referenced
 modules are not interchangeable, but the difference between them does
 not affect how the substitute definition is interpreted.
    Aside: There are many ways in which the substitute definition can
    be unaffected by a difference between the contexts of the
    referencing and referenced modules.  One example would be where
    the referencing and referenced modules differ only in their
    TagDefault, but the substitute definition does not contain any
    TaggedType notation.
 Note that if the translation in case (a) is used, then the
 referencing module is still the referencing module when considering a
 nested in-line expansion.  If the translation in case (b) is used,
 then the referenced module becomes the referencing module when
 considering a nested in-line expansion.

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 If case (a) is used for the translation of a DummyReference where the
 substitute definition is a Type, then an attribute form translation
 of the substitute definition SHALL NOT be used, and an attribute item
 with the [local name] "explicit" and [normalized value] "true" or "1"
 SHALL be added to the [attributes] of the <type> element item
 resulting from the translation of the substitute definition.  Where
 the automatic tagging transformation applies [X.680], this attribute
 item indicates that explicit tagging applies to the type instead of
 the usual implicit tagging.
 If case (b) is used for the translation of a DummyReference where the
 substitute definition is a Type, then an attribute item with the
 [local name] "explicit" and [normalized value] "true" or "1" SHALL be
 added to the [attributes] of the <type> element item generated by
 case (b).
 A fully expanded reference is an element item with the [local name]
 "expanded".  Except in the case of a DummyReference, the reference
 name is indicated by an attribute item with the [local name] "name"
 added to the [attributes] of the <expanded> element item.
 In the case of a ParameterizedType or ParameterizedValueSetType, the
 [normalized value] of this attribute item is the typereference of the
 ParameterizedType or ParameterizedValueSetType.
 In the case of a ParameterizedValue, the [normalized value] of this
 attribute item is the valuereference of the ParameterizedValue.
 In the case of a ParameterizedObjectClass, the [normalized value] of
 this attribute item is the objectclassreference of the
 ParameterizedObjectClass.
 In the case of a ParameterizedObject, the [normalized value] of this
 attribute item is the objectreference of the ParameterizedObject.
 In the case of a ParameterizedObjectSet, the [normalized value] of
 this attribute item is the objectsetreference of the
 ParameterizedObjectSet.
 The "name" attribute item MAY be omitted if:
 (1) the conditions permitting the use of the translation in case (a)
     are satisfied, or
 (2) the reference is not a typereference, or

Legg Experimental [Page 87] RFC 4912 Abstract Syntax Notation X July 2007

 (3) the reference is a typereference that does not appear in any
     TargetList in an XER encoding control section of the referenced
     module.
 The "name" attribute SHALL NOT appear in the translation of a
 DummyReference.
 The referenced module is indicated by an element item with the
 [local name] "module" added to the [children] of the <expanded>
 element item.  The <module> element item MAY be omitted if the
 conditions permitting the use of the translation in case (a) are
 satisfied, or if the referencing module is the referenced module.
 When the <module> element item is present:
 (1) An attribute item with the [local name] "name" SHOULD be added to
     the [attributes] of the <module> element item.  The
     [normalized value] of this attribute item is the modulereference
     in the ModuleIdentifier in the ModuleDefinition of the referenced
     module.
 (2) If the DefinitiveIdentifier in the ModuleIdentifier in the
     ModuleDefinition of the referenced module is not empty, then an
     attribute item with the [local name] "identifier" SHALL be added
     to the [attributes] of the <module> element item.  The
     [normalized value] of this attribute item is the RXER character
     data translation of the DefinitiveIdentifier.
 (3) If the referenced module has a schema identity URI, then an
     attribute item with the [local name] "schemaIdentity" SHALL be
     added to the [attributes] of the <module> element item.  The
     [normalized value] of this attribute item is the schema identity
     URI of the referenced module.
 The [attributes] of the <module> element item MUST contain at least
 one of the attribute items specified in cases (1), (2), and (3).
 The translation of the substitute definition SHALL be added to the
 [children] or [attributes] of the <expanded> element item.

Legg Experimental [Page 88] RFC 4912 Abstract Syntax Notation X July 2007

 Example
    Consider these module definitions:
       Templates
       DEFINITIONS
       AUTOMATIC TAGS ::=
       BEGIN
       CollectionOfThings { Thing } ::= SEQUENCE OF thing Thing
           -- the Thing on the right-hand side of the assignment is
           -- a DummyReference
       END
       ProtocolDefinitions
       DEFINITIONS
       AUTOMATIC TAGS ::=
       BEGIN
       IMPORTS
           CollectionOfThings{}
               FROM Templates
           ;
       CollectionOfIntegers ::= CollectionOfThings { INTEGER }
           -- the right-hand side of the assignment is
           -- a ParameterizedType
       END
    Without using the translation in case (a), the translations of
    these modules are:
       <asnx:module name="Templates"/>
       <asnx:module xmlns:asnx="urn:ietf:params:xml:ns:asnx"
                    name="ProtocolDefinitions">
        <namedType name="CollectionOfIntegers">
         <type>
          <expanded name="CollectionOfThings">
           <module name="Templates"/>
           <type>
            <sequenceOf>
             <element name="thing">
              <type>
               <expanded>

Legg Experimental [Page 89] RFC 4912 Abstract Syntax Notation X July 2007

                <module name="ProtocolDefinitions"/>
                <type ref="asnx:INTEGER"/>
               </expanded>
              </type>
             </element>
            </sequenceOf>
           </type>
          </expanded>
         </type>
        </namedType>
       </asnx:module>
    The translation of the Templates module is empty because the
    module contains only a parameterized assignment.
    Since the contexts of the Templates and ProtocolDefinitions
    modules are interchangeable, a simpler translation of the
    ProtocolDefinitions module is permitted:
       <asnx:module xmlns:asnx="urn:ietf:params:xml:ns:asnx"
                    name="ProtocolDefinitions">
        <namedType name="CollectionOfIntegers">
         <type>
          <sequenceOf>
           <element name="thing">
            <type ref="asnx:INTEGER" explicit="true"/>
           </element>
          </sequenceOf>
         </type>
        </namedType>
       </asnx:module>
 If a ParameterizedType or ParameterizedValueSetType is recursively
 contained, then its translation is an element item with the
 [local name] "type".  An attribute item with the [local name]
 "ancestor" SHALL be added to the [attributes] of the <type> element
 item.  The [normalized value] of this attribute item is the decimal
 digit string representing the integer value of one plus the number of
 intermediate enclosing <type> element items between the <type>
 element items resulting from the translations of the two equivalent
 instances of ParameterizedType or ParameterizedValueSetType.  An
 element item with the [local name] "annotation" MAY be added to the
 [children] of the <type> element item.

Legg Experimental [Page 90] RFC 4912 Abstract Syntax Notation X July 2007

 A <type> element item with an ancestor attribute item is a reference
 to an ancestor <type> element item.  This form for a <type> element
 item SHOULD NOT be used in original specifications written in ASN.X.
    Aside: The form is only intended for the purpose of handling
    recursive parameterized type definitions in an ASN.1 specification
    being translated into ASN.X.  Such definitions are
    self-referencing, but have no obvious name.  It is also not easy
    to construct a suitable name from the surrounding context because
    recursive parameterized types can be embedded in other constructs,
    such as information objects, that are themselves unnamed.
 Example
    Consider these type definitions, assumed to be defined in a module
    that does not have an XER encoding control section:
       Tree { ValueType } ::= SEQUENCE {
           value          [0] ValueType,
           left-subtree   [1] Tree { ValueType } OPTIONAL,
           right-subtree  [2] Tree { ValueType } OPTIONAL
       }
       NumberTree ::= [APPLICATION 13] Tree { INTEGER }
    The assignment for "Tree" is not directly translated because it is
    a ParameterizedAssignment.  The translation for the "NumberTree"
    assignment, up to but not yet including the Type in the
    TaggedType, is as follows:
       <namedType name="NumberTree">
        <type>
         <tagged tagClass="application" number="13"/>
        </type>
       </namedType>
    The Type in the TaggedType is a ParameterizedType.  Since the
    ParameterizedType is not recursively contained, the translation of
    the ParameterizedType (using the translation in case (a) above) is
    the translation of the Type on the right-hand side of the
    referenced ParameterizedTypeAssignment, namely this type:
       SEQUENCE {
           value          [0] ValueType,
           left-subtree   [1] Tree { ValueType } OPTIONAL,
           right-subtree  [2] Tree { ValueType } OPTIONAL
       }

Legg Experimental [Page 91] RFC 4912 Abstract Syntax Notation X July 2007

    ValueType is a DummyReference.  The translation of the actual
    parameter substitutes for the DummyReference.  In this case, the
    actual parameter is the INTEGER type.
    The translation for the SEQUENCE type, up to the first component,
    is added to the <tagged> element:
       <namedType name="NumberTree">
        <type>
         <tagged tagClass="application" number="13">
          <type><!-- Tree { INTEGER } -->
           <sequence>
            <element name="value">
             <type>
              <tagged number="0">
               <type ref="asnx:INTEGER"
                     explicit="true"/><!-- ValueType -->
              </tagged>
             </type>
            </element>
           </sequence>
          </type>
         </tagged>
        </type>
       </namedType>
    The Type in the TaggedType for the second component is a
    ParameterizedType.  Since this ParameterizedType is recursively
    contained, its translation is a <type> element with the ancestor
    attribute.  The value of the ancestor attribute is "2" because
    there is one intermediate <type> element (for a TaggedType).  Put
    another way, the translations of the equivalent instances of
    ParameterizedType are two <type> steps apart.
    The translation of the third component of the SEQUENCE type
    follows the same pattern as the second component.  The completed
    translation is as follows:
       <namedType name="NumberTree">
        <type>
         <tagged tagClass="application" number="13">
          <type><!-- Tree { INTEGER } -->
           <sequence>
            <element name="value">
             <type>
              <tagged number="0">
               <type ref="asnx:INTEGER"
                     explicit="true"/><!-- ValueType -->

Legg Experimental [Page 92] RFC 4912 Abstract Syntax Notation X July 2007

              </tagged>
             </type>
            </element>
            <optional>
             <element name="left-subtree">
              <type>
               <tagged number="1">
                <type ancestor="2"/><!-- Tree { ValueType } -->
               </tagged>
              </type>
             </element>
            </optional>
            <optional>
             <element name="right-subtree">
              <type>
               <tagged number="2">
                <type ancestor="2"/><!-- Tree { ValueType } -->
               </tagged>
              </type>
             </element>
            </optional>
           </sequence>
          </type>
         </tagged>
        </type>
       </namedType>

14. EncodingControlSections Translation

 If an EncodingControlSections instance contains at least one
 EncodingControlSection with an encodingreference that is not RXER,
 then the translation of the EncodingControlSections instance is an
 element item with the [local name] "encodingControls".  The
 translation of each EncodingControlSection with an encodingreference
 that is not RXER SHALL be appended to the [children] of the
 <encodingControls> element item.
    Aside: This is not suggesting that RXER encoding control sections
    are ignored.  Encoding control sections for RXER are not
    explicitly represented in ASN.X, but rather affect how an ASN.1
    module is translated into an ASN.X module.  The effect of an RXER
    encoding control section on the translation is addressed in other
    parts of this specification.
    Encoding control sections for other encoding rules will have
    explicit representations in ASN.X.

Legg Experimental [Page 93] RFC 4912 Abstract Syntax Notation X July 2007

 If the encodingreference in an EncodingControlSection is GSER, then
 the translation of the EncodingControlSection is an element item with
 the [local name] "GSER".  The translation of the
 EncodingInstructionAssignmentList in the EncodingControlSection SHALL
 be added to the [children] of the <GSER> element item.
 The EncodingInstructionAssignmentList notation is different for each
 set of encoding instructions.  The translation into ASN.X of an
 EncodingInstructionAssignmentList for GSER is specified in a separate
 document [GSEREIT].
    Aside: The translation of an EncodingInstructionAssignmentList for
    GSER, as it is currently defined, is always empty.
 If the encodingreference in an EncodingControlSection is XER, then
 the translation of the EncodingControlSection is an element item with
 the [local name] "XER".  The translation of the
 EncodingInstructionAssignmentList in the EncodingControlSection SHALL
 be added to the [children] of the <XER> element item.  The
 translation into ASN.X of an EncodingInstructionAssignmentList for
 XER is specified in a separate document [XEREIT].

15. Security Considerations

 The ASN.X translation of an ASN.1 specification is semantically
 equivalent to the original ASN.1 specification.  The security
 considerations that apply to an application built from the original
 ASN.1 specification apply equally to an application built from the
 ASN.X translation.
 Syntax-based canonicalization for XML documents (e.g., Canonical XML
 [CXML]) depends on the Infoset of an XML document being preserved.
 However, the Infoset representation of an ASN.X module potentially
 changes if it is decoded and re-encoded (though its ASN.1 value is
 preserved), disrupting the Canonical XML representation.  To avoid
 this problem, ASN.X modules MUST be normalized prior to the
 application of syntax-based canonicalization.  The normalization
 rules can be found in Section 6.13 of the specification for RXER
 [RXER].

16. Acknowledgements

 The technology described in this document is the product of a
 research project begun jointly by Adacel Technologies Limited and
 Deakin University, and subsequently refined and completed by eB2Bcom.

Legg Experimental [Page 94] RFC 4912 Abstract Syntax Notation X July 2007

17. References

17.1. Normative References

 [BCP14]    Bradner, S., "Key words for use in RFCs to Indicate
            Requirement Levels", BCP 14, RFC 2119, March 1997.
 [URI]      Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform
            Resource Identifiers (URI): Generic Syntax", STD 66, RFC
            3986, January 2005.
 [GSER]     Legg, S., "Generic String Encoding Rules (GSER) for ASN.1
            Types", RFC 3641, October 2003.
 [GSEREI]   Legg, S., "Encoding Instructions for the Generic String
            Encoding Rules (GSER)", RFC 4792, January 2007.
 [RXER]     Legg, S. and D. Prager, "Robust XML Encoding Rules (RXER)
            for Abstract Syntax Notation One (ASN.1)",
             RFC 4910, July 2007.
 [RXEREI]   Legg, S., "Encoding Instructions for the Robust XML
            Encoding Rules (RXER)",
             RFC 4911, July 2007.
 [GSEREIT]  Legg, S., "Abstract Syntax Notation X (ASN.X)
            Representation of Encoding Instructions for the Generic
            String Encoding Rules (GSER)",
             RFC 4913, July 2007.
 [XEREIT]   Legg, S., "Abstract Syntax Notation X (ASN.X)
            Representation of Encoding Instructions for the XML
            Encoding Rules (XER)",
             RFC 4914, July 2007.
 [X.680]    ITU-T Recommendation X.680 (07/02) | ISO/IEC 8824-1,
            Information technology - Abstract Syntax Notation One
            (ASN.1):  Specification of basic notation.
 [X.680-1]  ITU-T Recommendation X.680 (2002) Amendment 1 (10/03) |
            ISO/IEC 8824-1:2002/Amd 1:2004, Support for EXTENDED-XER.
 [X.681]    ITU-T Recommendation X.681 (07/02) | ISO/IEC 8824-2,
            Information technology - Abstract Syntax Notation One
            (ASN.1):  Information object specification.

Legg Experimental [Page 95] RFC 4912 Abstract Syntax Notation X July 2007

 [X.682]    ITU-T Recommendation X.682 (07/02) | ISO/IEC 8824-3,
            Information technology - Abstract Syntax Notation One
            (ASN.1):  Constraint specification.
 [X.683]    ITU-T Recommendation X.683 (07/02) | ISO/IEC 8824-4,
            Information technology - Abstract Syntax Notation One
            (ASN.1):  Parameterization of ASN.1 specifications.
 [X.693]    ITU-T Recommendation X.693 (12/01) | ISO/IEC 8825-4:2002,
            Information technology - ASN.1 encoding rules: XML
            encoding rules (XER).
 [X.693-1]  Amendment 1: (to ITU-T Rec. X.693 | ISO/IEC 8825-4) XER
            encoding instructions and EXTENDED-XER.
 [XML10]    Bray, T., Paoli, J., Sperberg-McQueen, C., Maler, E. and
            F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fourth
            Edition)", W3C Recommendation,
            http://www.w3.org/TR/2006/REC-xml-20060816, August 2006.
 [XML11]    Bray, T., Paoli, J., Sperberg-McQueen, C., Maler, E.,
            Yergeau, F., and J. Cowan, "Extensible Markup Language
            (XML) 1.1 (Second Edition)", W3C Recommendation,
            http://www.w3.org/TR/2006/REC-xml11-20060816, August 2006.
 [XMLNS10]  Bray, T., Hollander, D., Layman, A., and R. Tobin,
            "Namespaces in XML 1.0 (Second Edition)", W3C
            Recommendation,
            http://www.w3.org/TR/2006/REC-xml-names-20060816, August
            2006.
 [XMLNS11]  Bray, T., Hollander, D., Layman, A. and R. Tobin,
            "Namespaces in XML 1.1 (Second Edition)", W3C
            Recommendation,
            http://www.w3.org/TR/2006/REC-xml-names11-20060816, August
            2006.
 [INFOSET]  Cowan, J. and R. Tobin, "XML Information Set (Second
            Edition)", W3C Recommendation,
            http://www.w3.org/TR/2004/REC-xml-infoset-20040204,
            February 2004.
 [UNICODE]  The Unicode Consortium, "The Unicode Standard, Version
            4.0", Boston, MA, Addison-Wesley Developers Press, 2003.
            ISBN 0-321-18578-1.

Legg Experimental [Page 96] RFC 4912 Abstract Syntax Notation X July 2007

17.2. Informative References

 [CXML]     Boyer, J., "Canonical XML Version 1.0", W3C
            Recommendation,
            http://www.w3.org/TR/2001/REC-xml-c14n-20010315, March
            2001.
 [XSD1]     Thompson, H., Beech, D., Maloney, M. and N. Mendelsohn,
            "XML Schema Part 1: Structures Second Edition", W3C
            Recommendation,
            http://www.w3.org/TR/2004/REC-xmlschema-1-20041028/,
            October 2004.
 [RNG]      Clark, J. and M. Makoto, "RELAX NG Tutorial", OASIS
            Committee Specification, http://www.oasis-open.org/
            committees/relax-ng/tutorial-20011203.html, December 2001.

Legg Experimental [Page 97] RFC 4912 Abstract Syntax Notation X July 2007

Appendix A. ASN.1 for ASN.X

 This appendix is normative.
 AbstractSyntaxNotation-X
     { iso(1) identified-organization(3) dod(6)
       internet(1) private(4) enterprise(1)
       xmled(21472) asnx(1) module(0) notation(1) }
  1. - Copyright (C) The IETF Trust (2007). This version of
  2. - this ASN.1 module is part of RFC 4912; see the RFC itself
  3. - for full legal notices.
  4. -
  5. - Regarding this ASN.1 module or any portion of it, the author
  6. - makes no guarantees and is not responsible for any damage
  7. - resulting from its use. The author grants irrevocable permission
  8. - to anyone to use, modify, and distribute it in any way that does
  9. - not diminish the rights of anyone else to use, modify, and
  10. - distribute it, provided that redistributed derivative works do
  11. - not contain misleading author or version information.
  12. - Derivative works need not be licensed under similar terms.
 DEFINITIONS
 RXER INSTRUCTIONS
 AUTOMATIC TAGS
 EXTENSIBILITY IMPLIED ::= BEGIN
 IMPORTS
     Markup,
     AnyURI,
     NCName,
     Name,
     QName
         FROM AdditionalBasicDefinitions
             { iso(1) identified-organization(3) dod(6)
               internet(1) private(4) enterprise(1)
               xmled(21472) asnx(1) module(0) basic(0) }
     GSER-EncodingInstruction,
     GSER-EncodingInstructionAssignmentList
         FROM GSER-EncodingInstructionNotation
             { iso(1) identified-organization(3) dod(6)
               internet(1) private(4) enterprise(1)
               xmled(21472) asnx(1) module(0) gser-ei-notation(2) }
     XER-EncodingInstruction,
     XER-EncodingInstructionAssignmentList
         FROM XER-EncodingInstructionNotation
             { iso(1) identified-organization(3) dod(6)
               internet(1) private(4) enterprise(1)

Legg Experimental [Page 98] RFC 4912 Abstract Syntax Notation X July 2007

               xmled(21472) asnx(1) module(0) xer-ei-notation(3) }
     ;
 ModuleDefinition ::= [HOLLOW-INSERTIONS] SEQUENCE {
     annotation            Annotation OPTIONAL,
     format                [ATTRIBUTE] [VERSION-INDICATOR]
                               UTF8String ("1.0", ...) DEFAULT "1.0",
     name                  [ATTRIBUTE] ModuleReference,
     identifier            [ATTRIBUTE] DefinitiveIdentifier OPTIONAL,
     schemaIdentity        [ATTRIBUTE] AnyURI OPTIONAL,
     targetNamespace       [ATTRIBUTE] AnyURI OPTIONAL,
     targetPrefix          [ATTRIBUTE] NCName OPTIONAL,
     tagDefault            [ATTRIBUTE] TagDefault DEFAULT automatic,
     extensibilityImplied  [ATTRIBUTE] BOOLEAN DEFAULT FALSE,
     export                SEQUENCE { } OPTIONAL,
         -- export is not used in this version
     imports               [GROUP] ImportList OPTIONAL,
     assignments           [GROUP] AssignmentList OPTIONAL,
     encodingControls      EncodingControlSections OPTIONAL
 }
 ModuleReference ::= TypeReference
 DefinitiveIdentifier ::= OBJECT IDENTIFIER
 TagDefault ::= ENUMERATED { explicit, implicit, automatic }
 Annotation ::= Markup
 ImportList ::= SEQUENCE SIZE (1..MAX) OF import Import
 Import ::= SEQUENCE {
     name            [ATTRIBUTE] ModuleReference OPTIONAL,
     identifier      [ATTRIBUTE] DefinitiveIdentifier OPTIONAL,
     schemaIdentity  [ATTRIBUTE] AnyURI OPTIONAL,
     namespace       [ATTRIBUTE] AnyURI OPTIONAL,
     schemaLocation  [ATTRIBUTE] AnyURI OPTIONAL
 }
 AssignmentList ::= SEQUENCE SIZE (1..MAX) OF
     assignment [GROUP] Assignment
 Assignment ::= [NO-INSERTIONS] CHOICE {
     namedType       TypeAssignment,
     namedValue      ValueAssignment,
     namedValueSet   ValueSetTypeAssignment,
     namedClass      ObjectClassAssignment,
     namedObject     ObjectAssignment,

Legg Experimental [Page 99] RFC 4912 Abstract Syntax Notation X July 2007

     namedObjectSet  ObjectSetAssignment,
     component       [GROUP] TopLevelNamedType
 }
 TypeAssignment ::= SEQUENCE {
     annotation  Annotation OPTIONAL,
     name        [ATTRIBUTE] TypeReference,
     type        [GROUP] Type
 }
 TypeReference ::= UTF8String (PATTERN "[A-Z]\w*(-\w+)*")
                               -- \w is equivalent to [a-zA-Z0-9]
 ValueAssignment ::= SEQUENCE {
     annotation  Annotation OPTIONAL,
     name        [ATTRIBUTE] ValueReference,
     type        [GROUP] Type,
     value       [GROUP] Value
 }
 ValueReference ::= Identifier
 Identifier ::= UTF8String (PATTERN "[a-z]\w(-\w+)*")
 ValueSetTypeAssignment ::= SEQUENCE {
     annotation  Annotation OPTIONAL,
     name        [ATTRIBUTE] TypeReference,
     type        [GROUP] Type,
     valueSet    [GROUP] ValueSet
 }
 ObjectClassAssignment ::= SEQUENCE {
     annotation   Annotation OPTIONAL,
     name         [ATTRIBUTE] ObjectClassReference,
     objectClass  [GROUP] ObjectClass
 }
 ObjectClassReference ::= UTF8String
                              (PATTERN "[A-Z][A-Z0-9]*(-[A-Z0-9]+)*")
 ObjectAssignment ::= SEQUENCE {
     annotation   Annotation OPTIONAL,
     name         [ATTRIBUTE] ObjectReference,
     objectClass  [GROUP] DefinedObjectClass,
     object       [GROUP] Object
 }
 ObjectReference ::= ValueReference

Legg Experimental [Page 100] RFC 4912 Abstract Syntax Notation X July 2007

 ObjectSetAssignment ::= SEQUENCE {
     annotation   Annotation OPTIONAL,
     name         [ATTRIBUTE] ObjectSetReference,
     objectClass  [GROUP] DefinedObjectClass,
     objectSet    [GROUP] ObjectSet
 }
 ObjectSetReference ::= TypeReference
 TopLevelNamedType ::= NamedType
     (WITH COMPONENTS { ...,
         component (WITH COMPONENTS { ...,
             definition (WITH COMPONENTS { ..., reference ABSENT })
         }),
         element   (WITH COMPONENTS { ...,
             definition (WITH COMPONENTS { ..., reference ABSENT })
         }),
         attribute (WITH COMPONENTS { ...,
             definition (WITH COMPONENTS { ..., reference ABSENT })
         }),
         group         ABSENT,
         member        ABSENT,
         item          ABSENT,
         simpleContent ABSENT })
 NamedType ::= [SINGULAR-INSERTIONS] CHOICE {
     component      Element,
     element        Element,
     attribute      Attribute,
     group          InvisibleNamedType,
     member         InvisibleNamedType,
     item           InvisibleNamedType,
     simpleContent  InvisibleNamedType
 }
 Attribute ::= GenericNamedType
     (WITH COMPONENTS { ...,
         definition (WITH COMPONENTS { ...,
             local (WITH COMPONENTS { ...,
                 typeAsVersion ABSENT }) }) })
 Element ::= GenericNamedType
     (WITH COMPONENTS { ...,
         definition (WITH COMPONENTS { ...,
             local (WITH COMPONENTS { ...,
                 versionIndicator ABSENT }) }) })

Legg Experimental [Page 101] RFC 4912 Abstract Syntax Notation X July 2007

 InvisibleNamedType ::= GenericNamedType
     (WITH COMPONENTS { ...,
         definition (WITH COMPONENTS { ...,
             reference  ABSENT,
             local (WITH COMPONENTS { ...,
                 typeAsVersion ABSENT,
                 versionIndicator ABSENT }) }) })
 GenericNamedType ::= [HOLLOW-INSERTIONS] SEQUENCE {
     annotation  Annotation OPTIONAL,
     identifier  [ATTRIBUTE] IdentifierOrEmpty OPTIONAL,
     definition  [GROUP] CHOICE {
         reference   [GROUP] DefinedComponent,
         local       [GROUP] LocalComponent
     }
 }
 IdentifierOrEmpty ::= UTF8String (INCLUDES Identifier | "")
 DefinedComponent ::= [HOLLOW-INSERTIONS] SEQUENCE {
     name         [GROUP] [NO-INSERTIONS] CHOICE {
         ref          [ATTRIBUTE] QName,
         elementType  [ATTRIBUTE] Name
     },
     namespace    [ATTRIBUTE] AnyURI OPTIONAL,
     context      [ATTRIBUTE] AnyURI OPTIONAL,
     embedded     [ATTRIBUTE] BOOLEAN OPTIONAL,
     prefixes     [GROUP] EncodingPrefixes OPTIONAL
 }
 (WITH COMPONENTS { ...,
      name (WITH COMPONENTS { ref PRESENT }),
      namespace ABSENT } |
  WITH COMPONENTS { ...,
      name (WITH COMPONENTS { elementType PRESENT }),
      embedded ABSENT })
 LocalComponent ::= SEQUENCE {
     name              [ATTRIBUTE] NCName,
     typeAsVersion     [ATTRIBUTE] BOOLEAN OPTIONAL,
     versionIndicator  [ATTRIBUTE] BOOLEAN OPTIONAL,
     type              [GROUP] Type
 }
 Type ::= [NO-INSERTIONS] CHOICE {
     typeRef  [NAME AS "type"] [ATTRIBUTE] QName,
     type     ElementFormType
 }

Legg Experimental [Page 102] RFC 4912 Abstract Syntax Notation X July 2007

 ElementFormType ::= [HOLLOW-INSERTIONS] SEQUENCE {
     annotation  Annotation OPTIONAL,
     explicit    [ATTRIBUTE] BOOLEAN OPTIONAL,
     definition  [GROUP] CHOICE {
         reference        [GROUP] DefinedType,
         expanded         ExpandedType,
         ancestor         [ATTRIBUTE] INTEGER (1..MAX),
         namedBitList     NamedBitList,
         namedNumberList  NamedNumberList,
         enumerated       EnumeratedType,
         tagged           TaggedType,
         prefixed         EncodingPrefixedType,
         selection        SelectionType,
         instanceOf       InstanceOfType,
         fromClass        ObjectClassFieldType,
         fromObjects      InformationFromObjects,
         sequence         SequenceType,
         set              SetType,
         choice           ChoiceType,
         union            UnionType,
         sequenceOf       SequenceOfType,
         setOf            SetOfType,
         list             ListType,
         constrained      ConstrainedType
     }
 }
 DefinedType ::= SEQUENCE {
     name       [GROUP] [NO-INSERTIONS] CHOICE {
         ref          [ATTRIBUTE] QName,
         elementType  [ATTRIBUTE] Name
     },
     context    [ATTRIBUTE] AnyURI OPTIONAL,
     embedded   [ATTRIBUTE] BOOLEAN OPTIONAL
 }
 (WITH COMPONENTS { ...,
      name (WITH COMPONENTS { ref PRESENT }) } |
  WITH COMPONENTS { ...,
      name (WITH COMPONENTS { elementType PRESENT }),
      embedded ABSENT })
 ExpandedType ::= SEQUENCE {
     name    [ATTRIBUTE] NCName OPTIONAL,
     module  ReferencedModule OPTIONAL,
     type    [GROUP] Type
 }
 ReferencedModule ::= SEQUENCE {

Legg Experimental [Page 103] RFC 4912 Abstract Syntax Notation X July 2007

     name            [ATTRIBUTE] ModuleReference OPTIONAL,
     identifier      [ATTRIBUTE] DefinitiveIdentifier OPTIONAL,
     schemaIdentity  [ATTRIBUTE] AnyURI OPTIONAL
 }
 NamedBitList ::= SEQUENCE SIZE (1..MAX) OF namedBit NamedBit
 NamedBit ::= SEQUENCE {
     name        [ATTRIBUTE] NCName,
     identifier  [ATTRIBUTE] Identifier OPTIONAL,
     bit         [ATTRIBUTE] INTEGER (0..MAX)
 }
 NamedNumberList ::= SEQUENCE SIZE (1..MAX) OF
     namedNumber NamedNumber
 NamedNumber ::= SEQUENCE {
     name        [ATTRIBUTE] NCName,
     identifier  [ATTRIBUTE] Identifier OPTIONAL,
     number      [ATTRIBUTE] INTEGER
 }
 EnumeratedType ::= SEQUENCE {
     root       [GROUP] Enumeration,
     extension  SEQUENCE {
         exception  ExceptionSpec OPTIONAL,
         additions  [GROUP] Enumeration OPTIONAL
     } OPTIONAL
 }
 Enumeration ::= SEQUENCE SIZE (1..MAX) OF
     enumeration EnumerationItem
 EnumerationItem ::= SEQUENCE {
     name        [ATTRIBUTE] NCName,
     identifier  [ATTRIBUTE] Identifier OPTIONAL,
     number      [ATTRIBUTE] INTEGER OPTIONAL
 }
 Tag ::= SEQUENCE {
     tagClass  [ATTRIBUTE] TagClass OPTIONAL,
     number    [ATTRIBUTE] INTEGER (0..MAX),
     tagging   [ATTRIBUTE] Tagging OPTIONAL
 }
 TaggedType ::= SEQUENCE {
     COMPONENTS OF Tag,
     type  [GROUP] Type

Legg Experimental [Page 104] RFC 4912 Abstract Syntax Notation X July 2007

 }
 TagClass ::= ENUMERATED { universal, application, private }
 Tagging ::= ENUMERATED { explicit, implicit }
 EncodingPrefixedType ::= [HOLLOW-INSERTIONS] SEQUENCE {
     prefixes  [GROUP] EncodingPrefixes,
     type      [GROUP] Type
 }
 EncodingPrefixes ::= SEQUENCE SIZE (1..MAX) OF
     prefix [GROUP] EncodingPrefix
 EncodingPrefix ::= [SINGULAR-INSERTIONS] CHOICE {
     tag   [NAME AS "TAG"] Tag,
     gser  [NAME AS "GSER"] GSER-EncodingInstruction,
     xer   [NAME AS "XER"] XER-EncodingInstruction
     -- plus encoding instructions
     -- for other encoding rules in the future
 }
 SelectionType ::= SEQUENCE {
     alternative  [GROUP] [SINGULAR-INSERTIONS] CHOICE {
         component    [ATTRIBUTE] QName,
         element      [ATTRIBUTE] QName,
         attribute    [ATTRIBUTE] QName,
         group        [ATTRIBUTE] QName,
         member       [ATTRIBUTE] QName
     },
     type         [GROUP] Type
 }
 InstanceOfType ::= DefinedObjectClass
 ObjectClassFieldType ::= SEQUENCE {
     objectClass  [GROUP] DefinedObjectClass,
     fieldName    [GROUP] FieldName
 }
 FieldName ::= [SINGULAR-INSERTIONS] CHOICE {
     fieldNameAtt  [NAME AS "fieldName"]
                       [ATTRIBUTE] PrimitiveFieldNames,
     fieldName     PrimitiveFieldNames
 }
 PrimitiveFieldNames ::= UTF8String

Legg Experimental [Page 105] RFC 4912 Abstract Syntax Notation X July 2007

 InformationFromObjects ::= [HOLLOW-INSERTIONS] SEQUENCE {
     referencedObjects  [GROUP] ReferencedObjects,
     fieldName          [GROUP] FieldName
 }
 ReferencedObjects ::= [SINGULAR-INSERTIONS] CHOICE {
     object     [GROUP] Object,
     objectSet  [GROUP] ObjectSet
 }
 Insertions ::=
     ENUMERATED { none, hollow, singular, uniform, multiform }
 SequenceType ::= [HOLLOW-INSERTIONS] SEQUENCE {
     insertions         [ATTRIBUTE] Insertions OPTIONAL,
     root               [GROUP] ComponentTypeList OPTIONAL,
     extensionAndFinal  [GROUP] [HOLLOW-INSERTIONS] SEQUENCE {
         extension          [HOLLOW-INSERTIONS] SEQUENCE {
             exception          ExceptionSpec OPTIONAL,
             additions          [GROUP] ExtensionAdditions OPTIONAL
         },
         root               [GROUP] ComponentTypeList OPTIONAL
     } OPTIONAL
 }
 ComponentTypeList ::= SEQUENCE SIZE (1..MAX) OF
     componentType [GROUP] ComponentType
 ComponentType ::= [NO-INSERTIONS] CHOICE {
     component     [GROUP] SequenceNamedType,
     optional      SEQUENCE {
         component     [GROUP] SequenceNamedType,
         default       Value OPTIONAL
     },
     componentsOf  Type
 }
 SequenceNamedType ::= NamedType
     (WITH COMPONENTS { ..., member ABSENT, item ABSENT })
 ExtensionAdditions ::= SEQUENCE SIZE (1..MAX) OF
     addition [GROUP] ExtensionAddition
 ExtensionAddition ::= [NO-INSERTIONS] CHOICE {
     extensionGroup  ExtensionAdditionGroup,
     componentType   [GROUP] ComponentType
 }

Legg Experimental [Page 106] RFC 4912 Abstract Syntax Notation X July 2007

 ExtensionAdditionGroup ::= [HOLLOW-INSERTIONS] SEQUENCE {
     version         [ATTRIBUTE] VersionNumber OPTIONAL,
     componentTypes  [GROUP] ComponentTypeList
 }
 VersionNumber ::= INTEGER (2..MAX)
 SetType ::= SequenceType
 ChoiceOrUnionType ::= [HOLLOW-INSERTIONS] SEQUENCE {
     insertions  [ATTRIBUTE] Insertions OPTIONAL,
     precedence  [ATTRIBUTE] PrecedenceList OPTIONAL,
     root        [GROUP] AlternativeTypeList,
     extension   [HOLLOW-INSERTIONS] SEQUENCE {
         exception   ExceptionSpec OPTIONAL,
         additions   [GROUP] ExtensionAdditionAlternatives OPTIONAL
     } OPTIONAL
 }
 PrecedenceList ::= [LIST] SEQUENCE SIZE (1..MAX) OF member QName
 AlternativeTypeList ::= SEQUENCE SIZE (1..MAX) OF
     component [GROUP] ChoiceOrUnionNamedType
 ChoiceOrUnionNamedType ::= NamedType
     (WITH COMPONENTS { ..., item ABSENT, simpleContent ABSENT })
 ExtensionAdditionAlternatives ::= SEQUENCE SIZE (1..MAX) OF
     addition [GROUP] ExtensionAdditionAlternative
 ExtensionAdditionAlternative ::= [NO-INSERTIONS] CHOICE {
     extensionGroup  ExtensionAdditionAlternativesGroup,
     component       [GROUP] ChoiceOrUnionNamedType
 }
 ExtensionAdditionAlternativesGroup ::= [HOLLOW-INSERTIONS] SEQUENCE {
     version       [ATTRIBUTE] VersionNumber OPTIONAL,
     alternatives  [GROUP] AlternativeTypeList
 }
 ChoiceType ::= ChoiceOrUnionType
     (WITH COMPONENTS { ...,
         precedence ABSENT,
         root (WITH COMPONENT (INCLUDES ChoiceNamedType)),
         extension (WITH COMPONENTS { ...,
             additions (WITH COMPONENT (WITH COMPONENTS { ...,
                 extensionGroup (WITH COMPONENTS { ...,
                     alternatives (WITH COMPONENT

Legg Experimental [Page 107] RFC 4912 Abstract Syntax Notation X July 2007

                         (INCLUDES ChoiceNamedType)) }),
                 component (INCLUDES ChoiceNamedType) })) }) })
 ChoiceNamedType ::= ChoiceOrUnionNamedType
     (WITH COMPONENTS { ..., member ABSENT })
 UnionType ::= ChoiceOrUnionType
     (WITH COMPONENTS { ...,
         insertions ABSENT,
         root (WITH COMPONENT (INCLUDES UnionNamedType)),
         extension (WITH COMPONENTS { ...,
             additions (WITH COMPONENT (WITH COMPONENTS { ...,
                 extensionGroup (WITH COMPONENTS { ...,
                     alternatives (WITH COMPONENT
                         (INCLUDES UnionNamedType)) }),
                 component (INCLUDES UnionNamedType) })) }) })
 UnionNamedType ::= ChoiceOrUnionNamedType
     (WITH COMPONENTS { ...,
         component ABSENT,
         element   ABSENT,
         attribute ABSENT,
         group     ABSENT })
 SequenceOfOrListType ::= SEQUENCE {
     minSize    [ATTRIBUTE] INTEGER (0..MAX) OPTIONAL,
     maxSize    [ATTRIBUTE] INTEGER (0..MAX) OPTIONAL,
     component  [GROUP] NamedType
                    (WITH COMPONENTS { ...,
                        attribute     ABSENT,
                        member        ABSENT,
                        simpleContent ABSENT })
 }
 SequenceOfType ::= SequenceOfOrListType
     (WITH COMPONENTS { ...,
         component (WITH COMPONENTS { ..., item ABSENT }) })
 SetOfType ::= SequenceOfType
 ListType ::= SequenceOfOrListType
     (WITH COMPONENTS { ...,
         component (WITH COMPONENTS { ...,
                       component ABSENT,
                       element   ABSENT,
                       group     ABSENT }) })
 ConstrainedType ::= [HOLLOW-INSERTIONS] SEQUENCE {

Legg Experimental [Page 108] RFC 4912 Abstract Syntax Notation X July 2007

     type        [GROUP] Type,
     constraint  [GROUP] Constraint
 }
 Constraint ::= SEQUENCE {
     constraintSpec  [GROUP] [NO-INSERTIONS] CHOICE {
         subtype         [GROUP] ElementSetSpecs,
         constrainedBy   UserDefinedConstraint,
         table           TableConstraint,
         contents        ContentsConstraint
     },
     exception       ExceptionSpec OPTIONAL
 }
 UserDefinedConstraint ::= [HOLLOW-INSERTIONS] SEQUENCE {
     annotation  Annotation OPTIONAL,
     parameters  [GROUP] ConstraintParameters OPTIONAL
 }
 ConstraintParameters ::= SEQUENCE SIZE (1..MAX) OF
     parameter [GROUP] UserDefinedConstraintParameter
 UserDefinedConstraintParameter ::= [SINGULAR-INSERTIONS] CHOICE {
     valueParameter      SEQUENCE {
         type                [GROUP] Type,
         value               [GROUP] Value
     },
     valueSetParameter   SEQUENCE {
         type                [GROUP] Type,
         valueSet            [GROUP] ValueSet
     },
     objectParameter     SEQUENCE {
         objectClass         [GROUP] DefinedObjectClass,
         object              [GROUP] Object
     },
     objectSetParameter  SEQUENCE {
         objectClass         [GROUP] DefinedObjectClass,
         objectSet           [GROUP] ObjectSet
     },
     typeParameter       SEQUENCE {
         type                [GROUP] Type
     },
     classParameter      SEQUENCE {
         objectClass         [GROUP] DefinedObjectClass
     }
 }
 TableConstraint ::= SEQUENCE {

Legg Experimental [Page 109] RFC 4912 Abstract Syntax Notation X July 2007

     objectSet          [GROUP] ObjectSet,
     componentRelation  [GROUP] AtNotations OPTIONAL
 }
 AtNotations ::= SEQUENCE SIZE (1..MAX) OF
     restrictBy AtNotation
 AtNotation ::= Markup
 ContentsConstraint ::= SEQUENCE {
     containing  Type OPTIONAL,
     encodedBy   Value OPTIONAL
 } ((WITH COMPONENTS { ..., containing PRESENT }) |
    (WITH COMPONENTS { ..., encodedBy PRESENT }))
 ExceptionSpec ::= SEQUENCE {
     type   [GROUP] Type,
     value  [GROUP] Value
 }
 Value ::= [NO-INSERTIONS] CHOICE {
     literalValueAtt  [NAME AS "literalValue"] [ATTRIBUTE] UTF8String,
     literalValue     ElementFormLiteralValue,
     valueRef         [NAME AS "value"] [ATTRIBUTE] QName,
     value            ElementFormNotationalValue
 }
 ElementFormLiteralValue ::= Markup
 -- If asnx:literal="false" then the governing type of
 -- ElementFormLiteralValue is ElementFormNotationalValue.
 ElementFormNotationalValue ::= [HOLLOW-INSERTIONS] SEQUENCE {
     annotation  Annotation OPTIONAL,
     definition  [GROUP] [NO-INSERTIONS] CHOICE {
         reference      [GROUP] Reference,
         expanded       ExpandedValue,
         fromObjects    InformationFromObjects,
         openTypeValue  SEQUENCE {
             type           [GROUP] Type,
             value          [GROUP] Value
         },
         components     [GROUP] ComponentValueList
     }
 }
 Reference ::= SEQUENCE {
     ref      [ATTRIBUTE] QName,
     context  [ATTRIBUTE] AnyURI OPTIONAL

Legg Experimental [Page 110] RFC 4912 Abstract Syntax Notation X July 2007

 }
 ExpandedValue ::= SEQUENCE {
     name    [ATTRIBUTE] NCName OPTIONAL,
     module  ReferencedModule OPTIONAL,
     value   [GROUP] Value
 }
 ComponentValueList ::= SEQUENCE SIZE (1..MAX) OF
     component [GROUP] NamedValue
 NamedValue ::= [SINGULAR-INSERTIONS] CHOICE {
     component      GenericNamedValue,
     element        GenericNamedValue,
     attribute      GenericNamedValue,
     group          GenericNamedValue,
     member         GenericNamedValue,
     item           GenericNamedValue,
     simpleContent  GenericNamedValue
 }
 GenericNamedValue ::= SEQUENCE {
     name   [ATTRIBUTE] QName,
     value  [GROUP] Value
 }
 ValueSet ::= [NO-INSERTIONS] CHOICE {
     valueSetRef  [NAME AS "valueSet"] [ATTRIBUTE] QName,
         -- valueSetRef is not used in this version
     valueSet     ElementFormValueSet
 }
 ElementFormValueSet ::= [HOLLOW-INSERTIONS] SEQUENCE {
     annotation  Annotation OPTIONAL,
     definition  [GROUP] [NO-INSERTIONS] CHOICE {
         elementSetSpecs  [GROUP] ElementSetSpecs
     }
 }
 ElementSetSpecs ::= [HOLLOW-INSERTIONS] SEQUENCE {
     root       [GROUP] ValueElementSetSpec,
     extension  [HOLLOW-INSERTIONS] SEQUENCE {
         additions  [GROUP] ValueElementSetSpec OPTIONAL
     } OPTIONAL
 }
 ValueElementSetSpec ::= ElementSetSpec
 (WITH COMPONENTS { ...,

Legg Experimental [Page 111] RFC 4912 Abstract Syntax Notation X July 2007

     object        ABSENT,
     objectSet     ABSENT,
     union         (WITH COMPONENT (INCLUDES ValueElementSetSpec)),
     intersection  (WITH COMPONENT (INCLUDES ValueElementSetSpec)),
     all           (WITH COMPONENTS { ...,
         elements      (INCLUDES ValueElementSetSpec),
         except        (INCLUDES ValueElementSetSpec) }) })
 ElementSetSpec ::= [SINGULAR-INSERTIONS] CHOICE {
     literalValue    ElementFormLiteralValue,
     value           ElementFormNotationalValue,
     includes        Type,
     range           ValueRange,
     size            Constraint,
     typeConstraint  Type,
     from            Constraint,
     withComponent   Constraint,
     withComponents  MultipleTypeConstraints,
     pattern         Value,
     object          ElementFormObject,
     objectSet       ElementFormObjectSet,
     union           ElementSetSpecList,
     intersection    ElementSetSpecList,
     all             SEQUENCE {
         elements        [GROUP] ElementSetSpec OPTIONAL,
         except          ElementSetSpec
     }
 }
 ElementSetSpecList ::= SEQUENCE SIZE (2..MAX) OF
     elements [GROUP] ElementSetSpec
 ValueRange ::= SEQUENCE {
     minimum  [GROUP] [NO-INSERTIONS] CHOICE {
         minInclusive  EndValue,
         minExclusive  EndValue
     } DEFAULT minInclusive:{},
     maximum  [GROUP] [NO-INSERTIONS] CHOICE {
         maxInclusive  EndValue,
         maxExclusive  EndValue
     } DEFAULT maxInclusive:{}
 }
 EndValue ::= [HOLLOW-INSERTIONS] SEQUENCE {
     value  [GROUP] Value OPTIONAL
 }
 MultipleTypeConstraints ::= [HOLLOW-INSERTIONS] SEQUENCE {

Legg Experimental [Page 112] RFC 4912 Abstract Syntax Notation X July 2007

     partial          [ATTRIBUTE] BOOLEAN DEFAULT FALSE,
     typeConstraints  [GROUP] TypeConstraints
 }
 TypeConstraints ::= SEQUENCE SIZE (1..MAX) OF
     namedConstraint [GROUP] NamedConstraint
 NamedConstraint ::= [SINGULAR-INSERTIONS] CHOICE {
     component      GenericNamedConstraint,
     element        GenericNamedConstraint,
     attribute      GenericNamedConstraint,
     group          GenericNamedConstraint,
     member         GenericNamedConstraint,
     item           GenericNamedConstraint,
     simpleContent  GenericNamedConstraint
 }
 GenericNamedConstraint ::= [HOLLOW-INSERTIONS] SEQUENCE {
     name        [ATTRIBUTE] QName,
     use         [ATTRIBUTE] PresenceConstraint OPTIONAL,
     constraint  [GROUP] Constraint OPTIONAL
 }
 PresenceConstraint ::= ENUMERATED { present, absent, optional }
 ObjectClass ::= [SINGULAR-INSERTIONS] CHOICE {
     classRef  [NAME AS "class"] [ATTRIBUTE] QName,
     class     ElementFormObjectClass
 }
 DefinedObjectClass ::= ObjectClass
     (WITH COMPONENTS { ...,
         class (WITH COMPONENTS { ...,
             definition (WITH COMPONENTS { ...,
                 objectClassDefn ABSENT }) }) })
 ElementFormObjectClass ::= [HOLLOW-INSERTIONS] SEQUENCE {
     annotation  Annotation OPTIONAL,
     definition  [GROUP] [NO-INSERTIONS] CHOICE {
         reference        [GROUP] Reference,
         expanded         ExpandedObjectClass,
         objectClassDefn  [GROUP] ObjectClassDefn
     }
 }
 ExpandedObjectClass ::= SEQUENCE {
     name         [ATTRIBUTE] NCName OPTIONAL,
     module       ReferencedModule OPTIONAL,

Legg Experimental [Page 113] RFC 4912 Abstract Syntax Notation X July 2007

     objectClass  [GROUP] ObjectClass
 }
 ObjectClassDefn ::= SEQUENCE SIZE (1..MAX) OF
     fieldSpec [GROUP] FieldSpec
 FieldSpec ::= [SINGULAR-INSERTIONS] CHOICE {
     typeField       TypeField,
     valueField      ValueField,
     valueSetField   ValueSetField,
     objectField     ObjectField,
     objectSetField  ObjectSetField,
     optional        OptionalField
 }
 OptionalField ::= SEQUENCE {
     field    [GROUP] [SINGULAR-INSERTIONS] CHOICE {
         typeField       TypeField,
         valueField      ValueField,
         valueSetField   ValueSetField,
         objectField     ObjectField,
         objectSetField  ObjectSetField
     },
     default  Setting OPTIONAL
 } (WITH COMPONENTS { ...,
       field (WITH COMPONENTS { typeField PRESENT }),
       default (WITH COMPONENTS { ...,
           value ABSENT,
           valueSet ABSENT,
           object ABSENT,
           objectSet ABSENT }) } |
    WITH COMPONENTS { ...,
       field (WITH COMPONENTS { valueField PRESENT }),
       default (WITH COMPONENTS { ...,
           type ABSENT,
           valueSet ABSENT,
           object ABSENT,
           objectSet ABSENT }) } |
    WITH COMPONENTS { ...,
       field (WITH COMPONENTS { valueSetField PRESENT }),
       default (WITH COMPONENTS { ...,
           type ABSENT,
           value ABSENT,
           object ABSENT,
           objectSet ABSENT }) } |
    WITH COMPONENTS { ...,
       field (WITH COMPONENTS { objectField PRESENT }),
       default (WITH COMPONENTS { ...,

Legg Experimental [Page 114] RFC 4912 Abstract Syntax Notation X July 2007

           type ABSENT,
           value ABSENT,
           valueSet ABSENT,
           objectSet ABSENT }) } |
    WITH COMPONENTS { ...,
       field (WITH COMPONENTS { objectSetField PRESENT }),
       default (WITH COMPONENTS { ...,
           type ABSENT,
           value ABSENT,
           valueSet ABSENT,
           object ABSENT }) })
 TypeField ::= SEQUENCE {
     annotation  Annotation OPTIONAL,
     name        [ATTRIBUTE] TypeFieldReference
 }
 TypeFieldReference ::= TypeReference
 ValueField ::= SEQUENCE {
     annotation  Annotation OPTIONAL,
     name        [ATTRIBUTE] ValueFieldReference,
     unique      [ATTRIBUTE] BOOLEAN OPTIONAL,
     governor    [GROUP] [SINGULAR-INSERTIONS] CHOICE {
         type           [GROUP] Type,
         typeFromField  FieldName
     }
 } ((WITH COMPONENTS { ..., unique ABSENT }) |
    (WITH COMPONENTS { ...,
        governor (WITH COMPONENTS { ..., typeFromField ABSENT }) }))
 ValueFieldReference ::= ValueReference
 ValueSetField ::= SEQUENCE {
     annotation  Annotation OPTIONAL,
     name        [ATTRIBUTE] ValueSetFieldReference,
     governor    [GROUP] [SINGULAR-INSERTIONS] CHOICE {
         type           [GROUP] Type,
         typeFromField  FieldName
     }
 }
 ValueSetFieldReference ::= TypeReference
 ObjectField ::= SEQUENCE {
     annotation   Annotation OPTIONAL,
     name         [ATTRIBUTE] ObjectFieldReference,
     objectClass  [GROUP] DefinedObjectClass

Legg Experimental [Page 115] RFC 4912 Abstract Syntax Notation X July 2007

 }
 ObjectFieldReference ::= ObjectReference
 ObjectSetField ::= SEQUENCE {
     annotation   Annotation OPTIONAL,
     name         [ATTRIBUTE] ObjectSetFieldReference,
     objectClass  [GROUP] DefinedObjectClass
 }
 ObjectSetFieldReference ::= ObjectSetReference
 Object ::= [NO-INSERTIONS] CHOICE {
     objectRef  [NAME AS "object"] [ATTRIBUTE] QName,
     object     ElementFormObject
 }
 ElementFormObject ::= [HOLLOW-INSERTIONS] SEQUENCE {
     annotation  Annotation OPTIONAL,
     definition  [GROUP] [SINGULAR-INSERTIONS] CHOICE {
         reference    [GROUP] Reference,
         expanded     ExpandedObject,
         fromObjects  InformationFromObjects,
         fields       [GROUP] ObjectDefn
     }
 }
 ExpandedObject ::= SEQUENCE {
     name    [ATTRIBUTE] NCName OPTIONAL,
     module  ReferencedModule OPTIONAL,
     object  [GROUP] Object
 }
 ObjectDefn ::= SEQUENCE OF field FieldSetting
 FieldSetting ::= [HOLLOW-INSERTIONS] SEQUENCE {
     name     [ATTRIBUTE] NCName,
     setting  [GROUP] Setting
 }
 Setting ::= CHOICE {
     type       [GROUP] Type,
     value      [GROUP] Value,
     valueSet   [GROUP] ValueSet,
     object     [GROUP] Object,
     objectSet  [GROUP] ObjectSet
 }

Legg Experimental [Page 116] RFC 4912 Abstract Syntax Notation X July 2007

 ObjectSet ::= [NO-INSERTIONS] CHOICE {
     objectSetRef  [NAME AS "objectSet"] [ATTRIBUTE] QName,
     objectSet     ElementFormObjectSet
 }
 ElementFormObjectSet ::= [HOLLOW-INSERTIONS] SEQUENCE {
     annotation  Annotation OPTIONAL,
     definition  [GROUP] [NO-INSERTIONS] CHOICE {
         reference      [GROUP] Reference,
         expanded       ExpandedObjectSet,
         objectSetSpec  [GROUP] ObjectSetSpec,
         fromObjects    InformationFromObjects
     }
 }
 ExpandedObjectSet ::= SEQUENCE {
     name       [ATTRIBUTE] NCName OPTIONAL,
     module     ReferencedModule OPTIONAL,
     objectSet  [GROUP] ObjectSet
 }
 ObjectSetSpec ::= [HOLLOW-INSERTIONS] SEQUENCE {
     root       [GROUP] ObjectElementSetSpec OPTIONAL,
     extension  [HOLLOW-INSERTIONS] SEQUENCE {
         additions  [GROUP] ObjectElementSetSpec OPTIONAL
     } OPTIONAL
 } ((WITH COMPONENTS { ..., root PRESENT }) |
    (WITH COMPONENTS { ..., extension PRESENT }))
 ObjectElementSetSpec ::= ElementSetSpec
 (WITH COMPONENTS { ...,
     literalValue    ABSENT,
     value           ABSENT,
     includes        ABSENT,
     range           ABSENT,
     size            ABSENT,
     typeConstraint  ABSENT,
     from            ABSENT,
     withComponent   ABSENT,
     withComponents  ABSENT,
     pattern         ABSENT,
     union           (WITH COMPONENT (INCLUDES ObjectElementSetSpec)),
     intersection    (WITH COMPONENT (INCLUDES ObjectElementSetSpec)),
     all             (WITH COMPONENTS { ...,
         elements        (INCLUDES ObjectElementSetSpec),
         except          (INCLUDES ObjectElementSetSpec) }) })
 EncodingControlSections ::= SEQUENCE SIZE (1..MAX) OF

Legg Experimental [Page 117] RFC 4912 Abstract Syntax Notation X July 2007

     section [GROUP] EncodingControlSection
 EncodingControlSection ::= [SINGULAR-INSERTIONS] CHOICE {
     gser  [NAME AS "GSER"] GSER-EncodingInstructionAssignmentList,
     xer   [NAME AS "XER"] XER-EncodingInstructionAssignmentList
     -- plus encoding control sections
     -- for other encoding rules in the future
 }
 ENCODING-CONTROL RXER
     SCHEMA-IDENTITY  "urn:oid:1.3.6.1.4.1.21472.1.0.1"
     TARGET-NAMESPACE "urn:ietf:params:xml:ns:asnx" PREFIX "asnx"
     COMPONENT module ModuleDefinition
     COMPONENT literal [ATTRIBUTE] BOOLEAN
 END

Appendix B. ASN.X for ASN.X

 This appendix is non-normative.
 <?xml version="1.0"?>
 <asnx:module xmlns:asnx="urn:ietf:params:xml:ns:asnx"
              name="AbstractSyntaxNotation-X"
              identifier="1.3.6.1.4.1.21472.1.0.1"
              schemaIdentity="urn:oid:1.3.6.1.4.1.21472.1.0.1"
              targetNamespace="urn:ietf:params:xml:ns:asnx"
              targetPrefix="asnx"
              extensibilityImplied="true">
  <annotation>
   Copyright (C) The IETF Trust (2007).  This version of
   this ASN.X module is part of RFC 4912; see the RFC itself
   for full legal notices.
   Regarding this ASN.X module or any portion of it, the author
   makes no guarantees and is not responsible for any damage
   resulting from its use.  The author grants irrevocable permission
   to anyone to use, modify, and distribute it in any way that does
   not diminish the rights of anyone else to use, modify, and
   distribute it, provided that redistributed derivative works do
   not contain misleading author or version information.
   Derivative works need not be licensed under similar terms.
  </annotation>

Legg Experimental [Page 118] RFC 4912 Abstract Syntax Notation X July 2007

  <import name="GSER-EncodingInstructionNotation"
          identifier="1.3.6.1.4.1.21472.1.0.2"
          schemaIdentity="urn:oid:1.3.6.1.4.1.21472.1.0.2"
          namespace="urn:ietf:params:xml:ns:asnx"/>
  <import name="XER-EncodingInstructionNotation"
          identifier="1.3.6.1.4.1.21472.1.0.3"
          schemaIdentity="urn:oid:1.3.6.1.4.1.21472.1.0.3"
          namespace="urn:ietf:params:xml:ns:asnx"/>
  <namedType name="ModuleDefinition">
   <type>
    <sequence insertions="hollow">
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <optional>
      <attribute name="format" versionIndicator="true">
       <type>
        <constrained type="asnx:UTF8String">
         <literalValue>1.0</literalValue>
         <extension/>
        </constrained>
       </type>
      </attribute>
      <default literalValue="1.0"/>
     </optional>
     <attribute name="name" type="asnx:ModuleReference"/>
     <optional>
      <attribute name="identifier" type="asnx:DefinitiveIdentifier"/>
     </optional>
     <optional>
      <attribute name="schemaIdentity" type="asnx:AnyURI"/>
     </optional>
     <optional>
      <attribute name="targetNamespace" type="asnx:AnyURI"/>
     </optional>
     <optional>
      <attribute name="targetPrefix" type="asnx:NCName"/>
     </optional>
     <optional>
      <attribute name="tagDefault" type="asnx:TagDefault"/>
      <default literalValue="automatic"/>
     </optional>
     <optional>
      <attribute name="extensibilityImplied" type="asnx:BOOLEAN"/>
      <default literalValue="false"/>
     </optional>

Legg Experimental [Page 119] RFC 4912 Abstract Syntax Notation X July 2007

     <optional>
      <element name="export">
       <annotation> export is not used in this version </annotation>
       <type>
        <sequence/>
       </type>
      </element>
     </optional>
     <optional>
      <group name="imports" type="asnx:ImportList"/>
     </optional>
     <optional>
      <group name="assignments" type="asnx:AssignmentList"/>
     </optional>
     <optional>
      <element name="encodingControls"
               type="asnx:EncodingControlSections"/>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="ModuleReference" type="asnx:TypeReference"/>
  <namedType name="DefinitiveIdentifier"
             type="asnx:OBJECT-IDENTIFIER"/>
  <namedType name="TagDefault">
   <type>
    <enumerated>
     <enumeration name="explicit"/>
     <enumeration name="implicit"/>
     <enumeration name="automatic"/>
    </enumerated>
   </type>
  </namedType>
  <namedType name="Annotation" type="asnx:Markup"/>
  <namedType name="ImportList">
   <type>
    <sequenceOf minSize="1">
     <element name="import" type="asnx:Import"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="Import">

Legg Experimental [Page 120] RFC 4912 Abstract Syntax Notation X July 2007

   <type>
    <sequence>
     <optional>
      <attribute name="name" type="asnx:ModuleReference"/>
     </optional>
     <optional>
      <attribute name="identifier" type="asnx:DefinitiveIdentifier"/>
     </optional>
     <optional>
      <attribute name="schemaIdentity" type="asnx:AnyURI"/>
     </optional>
     <optional>
      <attribute name="namespace" type="asnx:AnyURI"/>
     </optional>
     <optional>
      <attribute name="schemaLocation" type="asnx:AnyURI"/>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="AssignmentList">
   <type>
    <sequenceOf minSize="1">
     <group name="assignment" type="asnx:Assignment"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="Assignment">
   <type>
    <choice insertions="none">
     <element name="namedType" type="asnx:TypeAssignment"/>
     <element name="namedValue" type="asnx:ValueAssignment"/>
     <element name="namedValueSet"
              type="asnx:ValueSetTypeAssignment"/>
     <element name="namedClass" type="asnx:ObjectClassAssignment"/>
     <element name="namedObject" type="asnx:ObjectAssignment"/>
     <element name="namedObjectSet" type="asnx:ObjectSetAssignment"/>
     <group name="component" type="asnx:TopLevelNamedType"/>
    </choice>
   </type>
  </namedType>
  <namedType name="TypeAssignment">
   <type>
    <sequence>
     <optional>

Legg Experimental [Page 121] RFC 4912 Abstract Syntax Notation X July 2007

      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <attribute name="name" type="asnx:TypeReference"/>
     <group name="type" type="asnx:Type"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="TypeReference">
   <type>
    <constrained type="asnx:UTF8String">
     <pattern literalValue="[A-Z]\w*(-\w+)*"/>
     <!-- \w is equivalent to [a-zA-Z0-9] -->
    </constrained>
   </type>
  </namedType>
  <namedType name="ValueAssignment">
   <type>
    <sequence>
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <attribute name="name" type="asnx:ValueReference"/>
     <group name="type" type="asnx:Type"/>
     <group name="value" type="asnx:Value"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ValueReference" type="asnx:Identifier"/>
  <namedType name="Identifier">
   <type>
    <constrained type="asnx:UTF8String">
     <pattern literalValue="[a-z]\w(-\w+)*"/>
    </constrained>
   </type>
  </namedType>
  <namedType name="ValueSetTypeAssignment">
   <type>
    <sequence>
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <attribute name="name" type="asnx:TypeReference"/>
     <group name="type" type="asnx:Type"/>

Legg Experimental [Page 122] RFC 4912 Abstract Syntax Notation X July 2007

     <group name="valueSet" type="asnx:ValueSet"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ObjectClassAssignment">
   <type>
    <sequence>
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <attribute name="name" type="asnx:ObjectClassReference"/>
     <group name="objectClass" type="asnx:ObjectClass"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ObjectClassReference">
   <type>
    <constrained type="asnx:UTF8String">
     <pattern literalValue="[A-Z][A-Z0-9]*(-[A-Z0-9]+)*"/>
    </constrained>
   </type>
  </namedType>
  <namedType name="ObjectAssignment">
   <type>
    <sequence>
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <attribute name="name" type="asnx:ObjectReference"/>
     <group name="objectClass" type="asnx:DefinedObjectClass"/>
     <group name="object" type="asnx:Object"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ObjectReference" type="asnx:ValueReference"/>
  <namedType name="ObjectSetAssignment">
   <type>
    <sequence>
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <attribute name="name" type="asnx:ObjectSetReference"/>
     <group name="objectClass" type="asnx:DefinedObjectClass"/>

Legg Experimental [Page 123] RFC 4912 Abstract Syntax Notation X July 2007

     <group name="objectSet" type="asnx:ObjectSet"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ObjectSetReference" type="asnx:TypeReference"/>
  <namedType name="TopLevelNamedType">
   <type>
    <constrained type="asnx:NamedType">
     <withComponents partial="true">
      <element name="component">
       <withComponents partial="true">
        <group name="definition">
         <withComponents partial="true">
          <group name="reference" use="absent"/>
         </withComponents>
        </group>
       </withComponents>
      </element>
      <element name="element">
       <withComponents partial="true">
        <group name="definition">
         <withComponents partial="true">
          <group name="reference" use="absent"/>
         </withComponents>
        </group>
       </withComponents>
      </element>
      <element name="attribute">
       <withComponents partial="true">
        <group name="definition">
         <withComponents partial="true">
          <group name="reference" use="absent"/>
         </withComponents>
        </group>
       </withComponents>
      </element>
      <element name="group" use="absent"/>
      <element name="member" use="absent"/>
      <element name="item" use="absent"/>
      <element name="simpleContent" use="absent"/>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="NamedType">

Legg Experimental [Page 124] RFC 4912 Abstract Syntax Notation X July 2007

   <type>
    <choice insertions="singular">
     <element name="component" type="asnx:Element"/>
     <element name="element" type="asnx:Element"/>
     <element name="attribute" type="asnx:Attribute"/>
     <element name="group" type="asnx:InvisibleNamedType"/>
     <element name="member" type="asnx:InvisibleNamedType"/>
     <element name="item" type="asnx:InvisibleNamedType"/>
     <element name="simpleContent" type="asnx:InvisibleNamedType"/>
    </choice>
   </type>
  </namedType>
  <namedType name="Attribute">
   <type>
    <constrained type="asnx:GenericNamedType">
     <withComponents partial="true">
      <group name="definition">
       <withComponents partial="true">
        <group name="local">
         <withComponents partial="true">
          <attribute name="typeAsVersion" use="absent"/>
         </withComponents>
        </group>
       </withComponents>
      </group>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="Element">
   <type>
    <constrained type="asnx:GenericNamedType">
     <withComponents partial="true">
      <group name="definition">
       <withComponents partial="true">
        <group name="local">
         <withComponents partial="true">
          <attribute name="versionIndicator" use="absent"/>
         </withComponents>
        </group>
       </withComponents>
      </group>
     </withComponents>
    </constrained>
   </type>
  </namedType>

Legg Experimental [Page 125] RFC 4912 Abstract Syntax Notation X July 2007

  <namedType name="InvisibleNamedType">
   <type>
    <constrained type="asnx:GenericNamedType">
     <withComponents partial="true">
      <group name="definition">
       <withComponents partial="true">
        <group name="reference" use="absent"/>
        <group name="local">
         <withComponents partial="true">
          <attribute name="typeAsVersion" use="absent"/>
          <attribute name="versionIndicator" use="absent"/>
         </withComponents>
        </group>
       </withComponents>
      </group>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="GenericNamedType">
   <type>
    <sequence insertions="hollow">
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <optional>
      <attribute name="identifier" type="asnx:IdentifierOrEmpty"/>
     </optional>
     <group name="definition">
      <type>
       <choice>
        <group name="reference" type="asnx:DefinedComponent"/>
        <group name="local" type="asnx:LocalComponent"/>
       </choice>
      </type>
     </group>
    </sequence>
   </type>
  </namedType>
  <namedType name="IdentifierOrEmpty">
   <type>
    <constrained type="asnx:UTF8String">
     <union>
      <includes type="asnx:Identifier"/>
      <literalValue></literalValue>
     </union>

Legg Experimental [Page 126] RFC 4912 Abstract Syntax Notation X July 2007

    </constrained>
   </type>
  </namedType>
  <namedType name="DefinedComponent">
   <type>
    <constrained>
     <type>
      <sequence insertions="hollow">
       <group name="name">
        <type>
         <choice insertions="none">
          <attribute name="ref" type="asnx:QName"/>
          <attribute name="elementType" type="asnx:Name"/>
         </choice>
        </type>
       </group>
       <optional>
        <attribute name="namespace" type="asnx:AnyURI"/>
       </optional>
       <optional>
        <attribute name="context" type="asnx:AnyURI"/>
       </optional>
       <optional>
        <attribute name="embedded" type="asnx:BOOLEAN"/>
       </optional>
       <optional>
        <group name="prefixes" type="asnx:EncodingPrefixes"/>
       </optional>
      </sequence>
     </type>
     <union>
      <withComponents partial="true">
       <group name="name">
        <withComponents>
         <attribute name="ref" use="present"/>
        </withComponents>
       </group>
       <attribute name="namespace" use="absent"/>
      </withComponents>
      <withComponents partial="true">
       <group name="name">
        <withComponents>
         <attribute name="elementType" use="present"/>
        </withComponents>
       </group>
       <attribute name="embedded" use="absent"/>
      </withComponents>

Legg Experimental [Page 127] RFC 4912 Abstract Syntax Notation X July 2007

     </union>
    </constrained>
   </type>
  </namedType>
  <namedType name="LocalComponent">
   <type>
    <sequence>
     <attribute name="name" type="asnx:NCName"/>
     <optional>
      <attribute name="typeAsVersion" type="asnx:BOOLEAN"/>
     </optional>
     <optional>
      <attribute name="versionIndicator" type="asnx:BOOLEAN"/>
     </optional>
     <group name="type" type="asnx:Type"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="Type">
   <type>
    <choice insertions="none">
     <attribute name="type" identifier="typeRef" type="asnx:QName"/>
     <element name="type" type="asnx:ElementFormType"/>
    </choice>
   </type>
  </namedType>
  <namedType name="ElementFormType">
   <type>
    <sequence insertions="hollow">
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <optional>
      <attribute name="explicit" type="asnx:BOOLEAN"/>
     </optional>
     <group name="definition">
      <type>
       <choice>
        <group name="reference" type="asnx:DefinedType"/>
        <element name="expanded" type="asnx:ExpandedType"/>
        <attribute name="ancestor">
         <type>
          <constrained type="asnx:INTEGER">
           <range>
            <minInclusive literalValue="1"/>

Legg Experimental [Page 128] RFC 4912 Abstract Syntax Notation X July 2007

           </range>
          </constrained>
         </type>
        </attribute>
        <element name="namedBitList" type="asnx:NamedBitList"/>
        <element name="namedNumberList" type="asnx:NamedNumberList"/>
        <element name="enumerated" type="asnx:EnumeratedType"/>
        <element name="tagged" type="asnx:TaggedType"/>
        <element name="prefixed" type="asnx:EncodingPrefixedType"/>
        <element name="selection" type="asnx:SelectionType"/>
        <element name="instanceOf" type="asnx:InstanceOfType"/>
        <element name="fromClass" type="asnx:ObjectClassFieldType"/>
        <element name="fromObjects"
                 type="asnx:InformationFromObjects"/>
        <element name="sequence" type="asnx:SequenceType"/>
        <element name="set" type="asnx:SetType"/>
        <element name="choice" type="asnx:ChoiceType"/>
        <element name="union" type="asnx:UnionType"/>
        <element name="sequenceOf" type="asnx:SequenceOfType"/>
        <element name="setOf" type="asnx:SetOfType"/>
        <element name="list" type="asnx:ListType"/>
        <element name="constrained" type="asnx:ConstrainedType"/>
       </choice>
      </type>
     </group>
    </sequence>
   </type>
  </namedType>
  <namedType name="DefinedType">
   <type>
    <constrained>
     <type>
      <sequence>
       <group name="name">
        <type>
         <choice insertions="none">
          <attribute name="ref" type="asnx:QName"/>
          <attribute name="elementType" type="asnx:Name"/>
         </choice>
        </type>
       </group>
       <optional>
        <attribute name="context" type="asnx:AnyURI"/>
       </optional>
       <optional>
        <attribute name="embedded" type="asnx:BOOLEAN"/>
       </optional>

Legg Experimental [Page 129] RFC 4912 Abstract Syntax Notation X July 2007

      </sequence>
     </type>
     <union>
      <withComponents partial="true">
       <group name="name">
        <withComponents>
         <attribute name="ref" use="present"/>
        </withComponents>
       </group>
      </withComponents>
      <withComponents partial="true">
       <group name="name">
        <withComponents>
         <attribute name="elementType" use="present"/>
        </withComponents>
       </group>
       <attribute name="embedded" use="absent"/>
      </withComponents>
     </union>
    </constrained>
   </type>
  </namedType>
  <namedType name="ExpandedType">
   <type>
    <sequence>
     <optional>
      <attribute name="name" type="asnx:NCName"/>
     </optional>
     <optional>
      <element name="module" type="asnx:ReferencedModule"/>
     </optional>
     <group name="type" type="asnx:Type"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ReferencedModule">
   <type>
    <sequence>
     <optional>
      <attribute name="name" type="asnx:ModuleReference"/>
     </optional>
     <optional>
      <attribute name="identifier" type="asnx:DefinitiveIdentifier"/>
     </optional>
     <optional>
      <attribute name="schemaIdentity" type="asnx:AnyURI"/>

Legg Experimental [Page 130] RFC 4912 Abstract Syntax Notation X July 2007

     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="NamedBitList">
   <type>
    <sequenceOf minSize="1">
     <element name="namedBit" type="asnx:NamedBit"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="NamedBit">
   <type>
    <sequence>
     <attribute name="name" type="asnx:NCName"/>
     <optional>
      <attribute name="identifier" type="asnx:Identifier"/>
     </optional>
     <attribute name="bit">
      <type>
       <constrained type="asnx:INTEGER">
        <range>
         <minInclusive literalValue="0"/>
        </range>
       </constrained>
      </type>
     </attribute>
    </sequence>
   </type>
  </namedType>
  <namedType name="NamedNumberList">
   <type>
    <sequenceOf minSize="1">
     <element name="namedNumber" type="asnx:NamedNumber"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="NamedNumber">
   <type>
    <sequence>
     <attribute name="name" type="asnx:NCName"/>
     <optional>
      <attribute name="identifier" type="asnx:Identifier"/>
     </optional>

Legg Experimental [Page 131] RFC 4912 Abstract Syntax Notation X July 2007

     <attribute name="number" type="asnx:INTEGER"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="EnumeratedType">
   <type>
    <sequence>
     <group name="root" type="asnx:Enumeration"/>
     <optional>
      <element name="extension">
       <type>
        <sequence>
         <optional>
          <element name="exception" type="asnx:ExceptionSpec"/>
         </optional>
         <optional>
          <group name="additions" type="asnx:Enumeration"/>
         </optional>
        </sequence>
       </type>
      </element>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="Enumeration">
   <type>
    <sequenceOf minSize="1">
     <element name="enumeration" type="asnx:EnumerationItem"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="EnumerationItem">
   <type>
    <sequence>
     <attribute name="name" type="asnx:NCName"/>
     <optional>
      <attribute name="identifier" type="asnx:Identifier"/>
     </optional>
     <optional>
      <attribute name="number" type="asnx:INTEGER"/>
     </optional>
    </sequence>
   </type>
  </namedType>

Legg Experimental [Page 132] RFC 4912 Abstract Syntax Notation X July 2007

  <namedType name="Tag">
   <type>
    <sequence>
     <optional>
      <attribute name="tagClass" type="asnx:TagClass"/>
     </optional>
     <attribute name="number">
      <type>
       <constrained type="asnx:INTEGER">
        <range>
         <minInclusive literalValue="0"/>
        </range>
       </constrained>
      </type>
     </attribute>
     <optional>
      <attribute name="tagging" type="asnx:Tagging"/>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="TaggedType">
   <type>
    <sequence>
     <componentsOf type="asnx:Tag"/>
     <group name="type" type="asnx:Type"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="TagClass">
   <type>
    <enumerated>
     <enumeration name="universal"/>
     <enumeration name="application"/>
     <enumeration name="private"/>
    </enumerated>
   </type>
  </namedType>
  <namedType name="Tagging">
   <type>
    <enumerated>
     <enumeration name="explicit"/>
     <enumeration name="implicit"/>
    </enumerated>
   </type>

Legg Experimental [Page 133] RFC 4912 Abstract Syntax Notation X July 2007

  </namedType>
  <namedType name="EncodingPrefixedType">
   <type>
    <sequence insertions="hollow">
     <group name="prefixes" type="asnx:EncodingPrefixes"/>
     <group name="type" type="asnx:Type"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="EncodingPrefixes">
   <type>
    <sequenceOf minSize="1">
     <group name="prefix" type="asnx:EncodingPrefix"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="EncodingPrefix">
   <type>
    <choice insertions="singular">
     <element name="TAG" identifier="tag" type="asnx:Tag"/>
     <element name="GSER" identifier="gser"
              type="asnx:GSER-EncodingInstruction"/>
     <element name="XER" identifier="xer"
              type="asnx:XER-EncodingInstruction"/>
     <!-- plus encoding instructions
          for other encoding rules in the future -->
    </choice>
   </type>
  </namedType>
  <namedType name="SelectionType">
   <type>
    <sequence>
     <group name="alternative">
      <type>
       <choice insertions="singular">
        <attribute name="component" type="asnx:QName"/>
        <attribute name="element" type="asnx:QName"/>
        <attribute name="attribute" type="asnx:QName"/>
        <attribute name="group" type="asnx:QName"/>
        <attribute name="member" type="asnx:QName"/>
       </choice>
      </type>
     </group>
     <group name="type" type="asnx:Type"/>

Legg Experimental [Page 134] RFC 4912 Abstract Syntax Notation X July 2007

    </sequence>
   </type>
  </namedType>
  <namedType name="InstanceOfType" type="asnx:DefinedObjectClass"/>
  <namedType name="ObjectClassFieldType">
   <type>
    <sequence>
     <group name="objectClass" type="asnx:DefinedObjectClass"/>
     <group name="fieldName" type="asnx:FieldName"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="FieldName">
   <type>
    <choice insertions="singular">
     <attribute name="fieldName" identifier="fieldNameAtt"
                type="asnx:PrimitiveFieldNames"/>
     <element name="fieldName" type="asnx:PrimitiveFieldNames"/>
    </choice>
   </type>
  </namedType>
  <namedType name="PrimitiveFieldNames" type="asnx:UTF8String"/>
  <namedType name="InformationFromObjects">
   <type>
    <sequence insertions="hollow">
     <group name="referencedObjects" type="asnx:ReferencedObjects"/>
     <group name="fieldName" type="asnx:FieldName"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ReferencedObjects">
   <type>
    <choice insertions="singular">
     <group name="object" type="asnx:Object"/>
     <group name="objectSet" type="asnx:ObjectSet"/>
    </choice>
   </type>
  </namedType>
  <namedType name="Insertions">
   <type>
    <enumerated>

Legg Experimental [Page 135] RFC 4912 Abstract Syntax Notation X July 2007

     <enumeration name="none"/>
     <enumeration name="hollow"/>
     <enumeration name="singular"/>
     <enumeration name="uniform"/>
     <enumeration name="multiform"/>
    </enumerated>
   </type>
  </namedType>
  <namedType name="SequenceType">
   <type>
    <sequence insertions="hollow">
     <optional>
      <attribute name="insertions" type="asnx:Insertions"/>
     </optional>
     <optional>
      <group name="root" type="asnx:ComponentTypeList"/>
     </optional>
     <optional>
      <group name="extensionAndFinal">
       <type>
        <sequence insertions="hollow">
         <element name="extension">
          <type>
           <sequence insertions="hollow">
            <optional>
             <element name="exception" type="asnx:ExceptionSpec"/>
            </optional>
            <optional>
             <group name="additions" type="asnx:ExtensionAdditions"/>
            </optional>
           </sequence>
          </type>
         </element>
         <optional>
          <group name="root" type="asnx:ComponentTypeList"/>
         </optional>
        </sequence>
       </type>
      </group>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="ComponentTypeList">
   <type>
    <sequenceOf minSize="1">

Legg Experimental [Page 136] RFC 4912 Abstract Syntax Notation X July 2007

     <group name="componentType" type="asnx:ComponentType"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="ComponentType">
   <type>
    <choice insertions="none">
     <group name="component" type="asnx:SequenceNamedType"/>
     <element name="optional">
      <type>
       <sequence>
        <group name="component" type="asnx:SequenceNamedType"/>
        <optional>
         <element name="default" type="asnx:Value"/>
        </optional>
       </sequence>
      </type>
     </element>
     <element name="componentsOf" type="asnx:Type"/>
    </choice>
   </type>
  </namedType>
  <namedType name="SequenceNamedType">
   <type>
    <constrained type="asnx:NamedType">
     <withComponents partial="true">
      <element name="member" use="absent"/>
      <element name="item" use="absent"/>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="ExtensionAdditions">
   <type>
    <sequenceOf minSize="1">
     <group name="addition" type="asnx:ExtensionAddition"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="ExtensionAddition">
   <type>
    <choice insertions="none">
     <element name="extensionGroup"
              type="asnx:ExtensionAdditionGroup"/>

Legg Experimental [Page 137] RFC 4912 Abstract Syntax Notation X July 2007

     <group name="componentType" type="asnx:ComponentType"/>
    </choice>
   </type>
  </namedType>
  <namedType name="ExtensionAdditionGroup">
   <type>
    <sequence insertions="hollow">
     <optional>
      <attribute name="version" type="asnx:VersionNumber"/>
     </optional>
     <group name="componentTypes" type="asnx:ComponentTypeList"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="VersionNumber">
   <type>
    <constrained type="asnx:INTEGER">
     <range>
      <minInclusive literalValue="2"/>
     </range>
    </constrained>
   </type>
  </namedType>
  <namedType name="SetType" type="asnx:SequenceType"/>
  <namedType name="ChoiceOrUnionType">
   <type>
    <sequence insertions="hollow">
     <optional>
      <attribute name="insertions" type="asnx:Insertions"/>
     </optional>
     <optional>
      <attribute name="precedence" type="asnx:PrecedenceList"/>
     </optional>
     <group name="root" type="asnx:AlternativeTypeList"/>
     <optional>
      <element name="extension">
       <type>
        <sequence insertions="hollow">
         <optional>
          <element name="exception" type="asnx:ExceptionSpec"/>
         </optional>
         <optional>
          <group name="additions"
                 type="asnx:ExtensionAdditionAlternatives"/>

Legg Experimental [Page 138] RFC 4912 Abstract Syntax Notation X July 2007

         </optional>
        </sequence>
       </type>
      </element>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="PrecedenceList">
   <type>
    <list minSize="1">
     <item name="member" type="asnx:QName"/>
    </list>
   </type>
  </namedType>
  <namedType name="AlternativeTypeList">
   <type>
    <sequenceOf minSize="1">
     <group name="component" type="asnx:ChoiceOrUnionNamedType"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="ChoiceOrUnionNamedType">
   <type>
    <constrained type="asnx:NamedType">
     <withComponents partial="true">
      <element name="item" use="absent"/>
      <element name="simpleContent" use="absent"/>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="ExtensionAdditionAlternatives">
   <type>
    <sequenceOf minSize="1">
     <group name="addition" type="asnx:ExtensionAdditionAlternative"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="ExtensionAdditionAlternative">
   <type>
    <choice insertions="none">
     <element name="extensionGroup"

Legg Experimental [Page 139] RFC 4912 Abstract Syntax Notation X July 2007

              type="asnx:ExtensionAdditionAlternativesGroup"/>
     <group name="component" type="asnx:ChoiceOrUnionNamedType"/>
    </choice>
   </type>
  </namedType>
  <namedType name="ExtensionAdditionAlternativesGroup">
   <type>
    <sequence insertions="hollow">
     <optional>
      <attribute name="version" type="asnx:VersionNumber"/>
     </optional>
     <group name="alternatives" type="asnx:AlternativeTypeList"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ChoiceType">
   <type>
    <constrained type="asnx:ChoiceOrUnionType">
     <withComponents partial="true">
      <attribute name="precedence" use="absent"/>
      <group name="root">
       <withComponent>
        <includes type="asnx:ChoiceNamedType"/>
       </withComponent>
      </group>
      <element name="extension">
       <withComponents partial="true">
        <group name="additions">
         <withComponent>
          <withComponents partial="true">
           <element name="extensionGroup">
            <withComponents partial="true">
             <group name="alternatives">
              <withComponent>
               <includes type="asnx:ChoiceNamedType"/>
              </withComponent>
             </group>
            </withComponents>
           </element>
           <group name="component">
            <includes type="asnx:ChoiceNamedType"/>
           </group>
          </withComponents>
         </withComponent>
        </group>
       </withComponents>

Legg Experimental [Page 140] RFC 4912 Abstract Syntax Notation X July 2007

      </element>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="ChoiceNamedType">
   <type>
    <constrained type="asnx:ChoiceOrUnionNamedType">
     <withComponents partial="true">
      <element name="member" use="absent"/>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="UnionType">
   <type>
    <constrained type="asnx:ChoiceOrUnionType">
     <withComponents partial="true">
      <attribute name="insertions" use="absent"/>
      <group name="root">
       <withComponent>
        <includes type="asnx:UnionNamedType"/>
       </withComponent>
      </group>
      <element name="extension">
       <withComponents partial="true">
        <group name="additions">
         <withComponent>
          <withComponents partial="true">
           <element name="extensionGroup">
            <withComponents partial="true">
             <group name="alternatives">
              <withComponent>
               <includes type="asnx:UnionNamedType"/>
              </withComponent>
             </group>
            </withComponents>
           </element>
           <group name="component">
            <includes type="asnx:UnionNamedType"/>
           </group>
          </withComponents>
         </withComponent>
        </group>
       </withComponents>
      </element>

Legg Experimental [Page 141] RFC 4912 Abstract Syntax Notation X July 2007

     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="UnionNamedType">
   <type>
    <constrained type="asnx:ChoiceOrUnionNamedType">
     <withComponents partial="true">
      <element name="component" use="absent"/>
      <element name="element" use="absent"/>
      <element name="attribute" use="absent"/>
      <element name="group" use="absent"/>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="SequenceOfOrListType">
   <type>
    <sequence>
     <optional>
      <attribute name="minSize">
       <type>
        <constrained type="asnx:INTEGER">
         <range>
          <minInclusive literalValue="0"/>
         </range>
        </constrained>
       </type>
      </attribute>
     </optional>
     <optional>
      <attribute name="maxSize">
       <type>
        <constrained type="asnx:INTEGER">
         <range>
          <minInclusive literalValue="0"/>
         </range>
        </constrained>
       </type>
      </attribute>
     </optional>
     <group name="component">
      <type>
       <constrained type="asnx:NamedType">
        <withComponents partial="true">
         <element name="attribute" use="absent"/>

Legg Experimental [Page 142] RFC 4912 Abstract Syntax Notation X July 2007

         <element name="member" use="absent"/>
         <element name="simpleContent" use="absent"/>
        </withComponents>
       </constrained>
      </type>
     </group>
    </sequence>
   </type>
  </namedType>
  <namedType name="SequenceOfType">
   <type>
    <constrained type="asnx:SequenceOfOrListType">
     <withComponents partial="true">
      <group name="component">
       <withComponents partial="true">
        <element name="item" use="absent"/>
       </withComponents>
      </group>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="SetOfType" type="asnx:SequenceOfType"/>
  <namedType name="ListType">
   <type>
    <constrained type="asnx:SequenceOfOrListType">
     <withComponents partial="true">
      <group name="component">
       <withComponents partial="true">
        <element name="component" use="absent"/>
        <element name="element" use="absent"/>
        <element name="group" use="absent"/>
       </withComponents>
      </group>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="ConstrainedType">
   <type>
    <sequence insertions="hollow">
     <group name="type" type="asnx:Type"/>
     <group name="constraint" type="asnx:Constraint"/>
    </sequence>

Legg Experimental [Page 143] RFC 4912 Abstract Syntax Notation X July 2007

   </type>
  </namedType>
  <namedType name="Constraint">
   <type>
    <sequence>
     <group name="constraintSpec">
      <type>
       <choice insertions="none">
        <group name="subtype" type="asnx:ElementSetSpecs"/>
        <element name="constrainedBy"
                 type="asnx:UserDefinedConstraint"/>
        <element name="table" type="asnx:TableConstraint"/>
        <element name="contents" type="asnx:ContentsConstraint"/>
       </choice>
      </type>
     </group>
     <optional>
      <element name="exception" type="asnx:ExceptionSpec"/>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="UserDefinedConstraint">
   <type>
    <sequence insertions="hollow">
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <optional>
      <group name="parameters" type="asnx:ConstraintParameters"/>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="ConstraintParameters">
   <type>
    <sequenceOf minSize="1">
     <group name="parameter"
            type="asnx:UserDefinedConstraintParameter"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="UserDefinedConstraintParameter">
   <type>

Legg Experimental [Page 144] RFC 4912 Abstract Syntax Notation X July 2007

    <choice insertions="singular">
     <element name="valueParameter">
      <type>
       <sequence>
        <group name="type" type="asnx:Type"/>
        <group name="value" type="asnx:Value"/>
       </sequence>
      </type>
     </element>
     <element name="valueSetParameter">
      <type>
       <sequence>
        <group name="type" type="asnx:Type"/>
        <group name="valueSet" type="asnx:ValueSet"/>
       </sequence>
      </type>
     </element>
     <element name="objectParameter">
      <type>
       <sequence>
        <group name="objectClass" type="asnx:DefinedObjectClass"/>
        <group name="object" type="asnx:Object"/>
       </sequence>
      </type>
     </element>
     <element name="objectSetParameter">
      <type>
       <sequence>
        <group name="objectClass" type="asnx:DefinedObjectClass"/>
        <group name="objectSet" type="asnx:ObjectSet"/>
       </sequence>
      </type>
     </element>
     <element name="typeParameter">
      <type>
       <sequence>
        <group name="type" type="asnx:Type"/>
       </sequence>
      </type>
     </element>
     <element name="classParameter">
      <type>
       <sequence>
        <group name="objectClass" type="asnx:DefinedObjectClass"/>
       </sequence>
      </type>
     </element>
    </choice>

Legg Experimental [Page 145] RFC 4912 Abstract Syntax Notation X July 2007

   </type>
  </namedType>
  <namedType name="TableConstraint">
   <type>
    <sequence>
     <group name="objectSet" type="asnx:ObjectSet"/>
     <optional>
      <group name="componentRelation" type="asnx:AtNotations"/>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="AtNotations">
   <type>
    <sequenceOf minSize="1">
     <element name="restrictBy" type="asnx:AtNotation"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="AtNotation" type="asnx:Markup"/>
  <namedType name="ContentsConstraint">
   <type>
    <constrained>
     <type>
      <sequence>
       <optional>
        <element name="containing" type="asnx:Type"/>
       </optional>
       <optional>
        <element name="encodedBy" type="asnx:Value"/>
       </optional>
      </sequence>
     </type>
     <union>
      <withComponents partial="true">
       <element name="containing" use="present"/>
      </withComponents>
      <withComponents partial="true">
       <element name="encodedBy" use="present"/>
      </withComponents>
     </union>
    </constrained>
   </type>
  </namedType>

Legg Experimental [Page 146] RFC 4912 Abstract Syntax Notation X July 2007

  <namedType name="ExceptionSpec">
   <type>
    <sequence>
     <group name="type" type="asnx:Type"/>
     <group name="value" type="asnx:Value"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="Value">
   <type>
    <choice insertions="none">
     <attribute name="literalValue" identifier="literalValueAtt"
                type="asnx:UTF8String"/>
     <element name="literalValue"
              type="asnx:ElementFormLiteralValue"/>
     <attribute name="value" identifier="valueRef" type="asnx:QName"/>
     <element name="value" type="asnx:ElementFormNotationalValue"/>
    </choice>
   </type>
  </namedType>
  <namedType name="ElementFormLiteralValue" type="asnx:Markup">
   <annotation>
    If asnx:literal="false" then the governing type of
    ElementFormLiteralValue is ElementFormNotationalValue.
   </annotation>
  </namedType>
  <namedType name="ElementFormNotationalValue">
   <type>
    <sequence insertions="hollow">
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <group name="definition">
      <type>
       <choice insertions="none">
        <group name="reference" type="asnx:Reference"/>
        <element name="expanded" type="asnx:ExpandedValue"/>
        <element name="fromObjects"
                 type="asnx:InformationFromObjects"/>
        <element name="openTypeValue">
         <type>
          <sequence>
           <group name="type" type="asnx:Type"/>
           <group name="value" type="asnx:Value"/>
          </sequence>

Legg Experimental [Page 147] RFC 4912 Abstract Syntax Notation X July 2007

         </type>
        </element>
        <group name="components" type="asnx:ComponentValueList"/>
       </choice>
      </type>
     </group>
    </sequence>
   </type>
  </namedType>
  <namedType name="Reference">
   <type>
    <sequence>
     <attribute name="ref" type="asnx:QName"/>
     <optional>
      <attribute name="context" type="asnx:AnyURI"/>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="ExpandedValue">
   <type>
    <sequence>
     <optional>
      <attribute name="name" type="asnx:NCName"/>
     </optional>
     <optional>
      <element name="module" type="asnx:ReferencedModule"/>
     </optional>
     <group name="value" type="asnx:Value"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ComponentValueList">
   <type>
    <sequenceOf minSize="1">
     <group name="component" type="asnx:NamedValue"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="NamedValue">
   <type>
    <choice insertions="singular">
     <element name="component" type="asnx:GenericNamedValue"/>
     <element name="element" type="asnx:GenericNamedValue"/>

Legg Experimental [Page 148] RFC 4912 Abstract Syntax Notation X July 2007

     <element name="attribute" type="asnx:GenericNamedValue"/>
     <element name="group" type="asnx:GenericNamedValue"/>
     <element name="member" type="asnx:GenericNamedValue"/>
     <element name="item" type="asnx:GenericNamedValue"/>
     <element name="simpleContent" type="asnx:GenericNamedValue"/>
    </choice>
   </type>
  </namedType>
  <namedType name="GenericNamedValue">
   <type>
    <sequence>
     <attribute name="name" type="asnx:QName"/>
     <group name="value" type="asnx:Value"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ValueSet">
   <type>
    <choice insertions="none">
     <attribute name="valueSet" identifier="valueSetRef"
                type="asnx:QName">
      <annotation>
       valueSet attribute is not used in this version
      </annotation>
     </attribute>
     <element name="valueSet" type="asnx:ElementFormValueSet"/>
    </choice>
   </type>
  </namedType>
  <namedType name="ElementFormValueSet">
   <type>
    <sequence insertions="hollow">
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <group name="definition">
      <type>
       <choice insertions="none">
        <group name="elementSetSpecs" type="asnx:ElementSetSpecs"/>
       </choice>
      </type>
     </group>
    </sequence>
   </type>
  </namedType>

Legg Experimental [Page 149] RFC 4912 Abstract Syntax Notation X July 2007

  <namedType name="ElementSetSpecs">
   <type>
    <sequence insertions="hollow">
     <group name="root" type="asnx:ValueElementSetSpec"/>
     <optional>
      <element name="extension">
       <type>
        <sequence insertions="hollow">
         <optional>
          <group name="additions" type="asnx:ValueElementSetSpec"/>
         </optional>
        </sequence>
       </type>
      </element>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="ValueElementSetSpec">
   <type>
    <constrained type="asnx:ElementSetSpec">
     <withComponents partial="true">
      <element name="object" use="absent"/>
      <element name="objectSet" use="absent"/>
      <element name="union">
       <withComponent>
        <includes type="asnx:ValueElementSetSpec"/>
       </withComponent>
      </element>
      <element name="intersection">
       <withComponent>
        <includes type="asnx:ValueElementSetSpec"/>
       </withComponent>
      </element>
      <element name="all">
       <withComponents partial="true">
        <group name="elements">
         <includes type="asnx:ValueElementSetSpec"/>
        </group>
        <element name="except">
         <includes type="asnx:ValueElementSetSpec"/>
        </element>
       </withComponents>
      </element>
     </withComponents>
    </constrained>
   </type>

Legg Experimental [Page 150] RFC 4912 Abstract Syntax Notation X July 2007

  </namedType>
  <namedType name="ElementSetSpec">
   <type>
    <choice insertions="singular">
     <element name="literalValue"
              type="asnx:ElementFormLiteralValue"/>
     <element name="value" type="asnx:ElementFormNotationalValue"/>
     <element name="includes" type="asnx:Type"/>
     <element name="range" type="asnx:ValueRange"/>
     <element name="size" type="asnx:Constraint"/>
     <element name="typeConstraint" type="asnx:Type"/>
     <element name="from" type="asnx:Constraint"/>
     <element name="withComponent" type="asnx:Constraint"/>
     <element name="withComponents"
              type="asnx:MultipleTypeConstraints"/>
     <element name="pattern" type="asnx:Value"/>
     <element name="object" type="asnx:ElementFormObject"/>
     <element name="objectSet" type="asnx:ElementFormObjectSet"/>
     <element name="union" type="asnx:ElementSetSpecList"/>
     <element name="intersection" type="asnx:ElementSetSpecList"/>
     <element name="all">
      <type>
       <sequence>
        <optional>
         <group name="elements" type="asnx:ElementSetSpec"/>
        </optional>
        <element name="except" type="asnx:ElementSetSpec"/>
       </sequence>
      </type>
     </element>
    </choice>
   </type>
  </namedType>
  <namedType name="ElementSetSpecList">
   <type>
    <sequenceOf minSize="2">
     <group name="elements" type="asnx:ElementSetSpec"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="ValueRange">
   <type>
    <sequence>
     <optional>
      <group name="minimum">

Legg Experimental [Page 151] RFC 4912 Abstract Syntax Notation X July 2007

       <type>
        <choice insertions="none">
         <element name="minInclusive" type="asnx:EndValue"/>
         <element name="minExclusive" type="asnx:EndValue"/>
        </choice>
       </type>
      </group>
      <default>
       <literalValue>
        <minInclusive/>
       </literalValue>
      </default>
     </optional>
     <optional>
      <group name="maximum">
       <type>
        <choice insertions="none">
         <element name="maxInclusive" type="asnx:EndValue"/>
         <element name="maxExclusive" type="asnx:EndValue"/>
        </choice>
       </type>
      </group>
      <default>
       <literalValue>
        <maxInclusive/>
       </literalValue>
      </default>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="EndValue">
   <type>
    <sequence insertions="hollow">
     <optional>
      <group name="value" type="asnx:Value"/>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="MultipleTypeConstraints">
   <type>
    <sequence insertions="hollow">
     <optional>
      <attribute name="partial" type="asnx:BOOLEAN"/>
      <default literalValue="false"/>

Legg Experimental [Page 152] RFC 4912 Abstract Syntax Notation X July 2007

     </optional>
     <group name="typeConstraints" type="asnx:TypeConstraints"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="TypeConstraints">
   <type>
    <sequenceOf minSize="1">
     <group name="namedConstraint" type="asnx:NamedConstraint"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="NamedConstraint">
   <type>
    <choice insertions="singular">
     <element name="component" type="asnx:GenericNamedConstraint"/>
     <element name="element" type="asnx:GenericNamedConstraint"/>
     <element name="attribute" type="asnx:GenericNamedConstraint"/>
     <element name="group" type="asnx:GenericNamedConstraint"/>
     <element name="member" type="asnx:GenericNamedConstraint"/>
     <element name="item" type="asnx:GenericNamedConstraint"/>
     <element name="simpleContent"
              type="asnx:GenericNamedConstraint"/>
    </choice>
   </type>
  </namedType>
  <namedType name="GenericNamedConstraint">
   <type>
    <sequence insertions="hollow">
     <attribute name="name" type="asnx:QName"/>
     <optional>
      <attribute name="use" type="asnx:PresenceConstraint"/>
     </optional>
     <optional>
      <group name="constraint" type="asnx:Constraint"/>
     </optional>
    </sequence>
   </type>
  </namedType>
  <namedType name="PresenceConstraint">
   <type>
    <enumerated>
     <enumeration name="present"/>
     <enumeration name="absent"/>

Legg Experimental [Page 153] RFC 4912 Abstract Syntax Notation X July 2007

     <enumeration name="optional"/>
    </enumerated>
   </type>
  </namedType>
  <namedType name="ObjectClass">
   <type>
    <choice insertions="singular">
     <attribute name="class" identifier="classRef" type="asnx:QName"/>
     <element name="class" type="asnx:ElementFormObjectClass"/>
    </choice>
   </type>
  </namedType>
  <namedType name="DefinedObjectClass">
   <type>
    <constrained type="asnx:ObjectClass">
     <withComponents partial="true">
      <element name="class">
       <withComponents partial="true">
        <group name="definition">
         <withComponents partial="true">
          <group name="objectClassDefn" use="absent"/>
         </withComponents>
        </group>
       </withComponents>
      </element>
     </withComponents>
    </constrained>
   </type>
  </namedType>
  <namedType name="ElementFormObjectClass">
   <type>
    <sequence insertions="hollow">
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <group name="definition">
      <type>
       <choice insertions="none">
        <group name="reference" type="asnx:Reference"/>
        <element name="expanded" type="asnx:ExpandedObjectClass"/>
        <group name="objectClassDefn" type="asnx:ObjectClassDefn"/>
       </choice>
      </type>
     </group>
    </sequence>

Legg Experimental [Page 154] RFC 4912 Abstract Syntax Notation X July 2007

   </type>
  </namedType>
  <namedType name="ExpandedObjectClass">
   <type>
    <sequence>
     <optional>
      <attribute name="name" type="asnx:NCName"/>
     </optional>
     <optional>
      <element name="module" type="asnx:ReferencedModule"/>
     </optional>
     <group name="objectClass" type="asnx:ObjectClass"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ObjectClassDefn">
   <type>
    <sequenceOf minSize="1">
     <group name="fieldSpec" type="asnx:FieldSpec"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="FieldSpec">
   <type>
    <choice insertions="singular">
     <element name="typeField" type="asnx:TypeField"/>
     <element name="valueField" type="asnx:ValueField"/>
     <element name="valueSetField" type="asnx:ValueSetField"/>
     <element name="objectField" type="asnx:ObjectField"/>
     <element name="objectSetField" type="asnx:ObjectSetField"/>
     <element name="optional" type="asnx:OptionalField"/>
    </choice>
   </type>
  </namedType>
  <namedType name="OptionalField">
   <type>
    <constrained>
     <type>
      <sequence>
       <group name="field">
        <type>
         <choice insertions="singular">
          <element name="typeField" type="asnx:TypeField"/>
          <element name="valueField" type="asnx:ValueField"/>

Legg Experimental [Page 155] RFC 4912 Abstract Syntax Notation X July 2007

          <element name="valueSetField" type="asnx:ValueSetField"/>
          <element name="objectField" type="asnx:ObjectField"/>
          <element name="objectSetField" type="asnx:ObjectSetField"/>
         </choice>
        </type>
       </group>
       <optional>
        <element name="default" type="asnx:Setting"/>
       </optional>
      </sequence>
     </type>
     <union>
      <withComponents partial="true">
       <group name="field">
        <withComponents>
         <element name="typeField" use="present"/>
        </withComponents>
       </group>
       <element name="default">
        <withComponents partial="true">
         <group name="value" use="absent"/>
         <group name="valueSet" use="absent"/>
         <group name="object" use="absent"/>
         <group name="objectSet" use="absent"/>
        </withComponents>
       </element>
      </withComponents>
      <withComponents partial="true">
       <group name="field">
        <withComponents>
         <element name="valueField" use="present"/>
        </withComponents>
       </group>
       <element name="default">
        <withComponents partial="true">
         <group name="type" use="absent"/>
         <group name="valueSet" use="absent"/>
         <group name="object" use="absent"/>
         <group name="objectSet" use="absent"/>
        </withComponents>
       </element>
      </withComponents>
      <withComponents partial="true">
       <group name="field">
        <withComponents>
         <element name="valueSetField" use="present"/>
        </withComponents>
       </group>

Legg Experimental [Page 156] RFC 4912 Abstract Syntax Notation X July 2007

       <element name="default">
        <withComponents partial="true">
         <group name="type" use="absent"/>
         <group name="value" use="absent"/>
         <group name="object" use="absent"/>
         <group name="objectSet" use="absent"/>
        </withComponents>
       </element>
      </withComponents>
      <withComponents partial="true">
       <group name="field">
        <withComponents>
         <element name="objectField" use="present"/>
        </withComponents>
       </group>
       <element name="default">
        <withComponents partial="true">
         <group name="type" use="absent"/>
         <group name="value" use="absent"/>
         <group name="valueSet" use="absent"/>
         <group name="objectSet" use="absent"/>
        </withComponents>
       </element>
      </withComponents>
      <withComponents partial="true">
       <group name="field">
        <withComponents>
         <element name="objectSetField" use="present"/>
        </withComponents>
       </group>
       <element name="default">
        <withComponents partial="true">
         <group name="type" use="absent"/>
         <group name="value" use="absent"/>
         <group name="valueSet" use="absent"/>
         <group name="object" use="absent"/>
        </withComponents>
       </element>
      </withComponents>
     </union>
    </constrained>
   </type>
  </namedType>
  <namedType name="TypeField">
   <type>
    <sequence>
     <optional>

Legg Experimental [Page 157] RFC 4912 Abstract Syntax Notation X July 2007

      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <attribute name="name" type="asnx:TypeFieldReference"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="TypeFieldReference" type="asnx:TypeReference"/>
  <namedType name="ValueField">
   <type>
    <constrained>
     <type>
      <sequence>
       <optional>
        <element name="annotation" type="asnx:Annotation"/>
       </optional>
       <attribute name="name" type="asnx:ValueFieldReference"/>
       <optional>
        <attribute name="unique" type="asnx:BOOLEAN"/>
       </optional>
       <group name="governor">
        <type>
         <choice insertions="singular">
          <group name="type" type="asnx:Type"/>
          <element name="typeFromField" type="asnx:FieldName"/>
         </choice>
        </type>
       </group>
      </sequence>
     </type>
     <union>
      <withComponents partial="true">
       <attribute name="unique" use="absent"/>
      </withComponents>
      <withComponents partial="true">
       <group name="governor">
        <withComponents partial="true">
         <element name="typeFromField" use="absent"/>
        </withComponents>
       </group>
      </withComponents>
     </union>
    </constrained>
   </type>
  </namedType>
  <namedType name="ValueFieldReference" type="asnx:ValueReference"/>

Legg Experimental [Page 158] RFC 4912 Abstract Syntax Notation X July 2007

  <namedType name="ValueSetField">
   <type>
    <sequence>
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <attribute name="name" type="asnx:ValueSetFieldReference"/>
     <group name="governor">
      <type>
       <choice insertions="singular">
        <group name="type" type="asnx:Type"/>
        <element name="typeFromField" type="asnx:FieldName"/>
       </choice>
      </type>
     </group>
    </sequence>
   </type>
  </namedType>
  <namedType name="ValueSetFieldReference" type="asnx:TypeReference"/>
  <namedType name="ObjectField">
   <type>
    <sequence>
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <attribute name="name" type="asnx:ObjectFieldReference"/>
     <group name="objectClass" type="asnx:DefinedObjectClass"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ObjectFieldReference" type="asnx:ObjectReference"/>
  <namedType name="ObjectSetField">
   <type>
    <sequence>
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <attribute name="name" type="asnx:ObjectSetFieldReference"/>
     <group name="objectClass" type="asnx:DefinedObjectClass"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ObjectSetFieldReference"

Legg Experimental [Page 159] RFC 4912 Abstract Syntax Notation X July 2007

             type="asnx:ObjectSetReference"/>
  <namedType name="Object">
   <type>
    <choice insertions="none">
     <attribute name="object" identifier="objectRef"
                type="asnx:QName"/>
     <element name="object" type="asnx:ElementFormObject"/>
    </choice>
   </type>
  </namedType>
  <namedType name="ElementFormObject">
   <type>
    <sequence insertions="hollow">
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <group name="definition">
      <type>
       <choice insertions="singular">
        <group name="reference" type="asnx:Reference"/>
        <element name="expanded" type="asnx:ExpandedObject"/>
        <element name="fromObjects"
                 type="asnx:InformationFromObjects"/>
        <group name="fields" type="asnx:ObjectDefn"/>
       </choice>
      </type>
     </group>
    </sequence>
   </type>
  </namedType>
  <namedType name="ExpandedObject">
   <type>
    <sequence>
     <optional>
      <attribute name="name" type="asnx:NCName"/>
     </optional>
     <optional>
      <element name="module" type="asnx:ReferencedModule"/>
     </optional>
     <group name="object" type="asnx:Object"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ObjectDefn">

Legg Experimental [Page 160] RFC 4912 Abstract Syntax Notation X July 2007

   <type>
    <sequenceOf>
     <element name="field" type="asnx:FieldSetting"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="FieldSetting">
   <type>
    <sequence insertions="hollow">
     <attribute name="name" type="asnx:NCName"/>
     <group name="setting" type="asnx:Setting"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="Setting">
   <type>
    <choice>
     <group name="type" type="asnx:Type"/>
     <group name="value" type="asnx:Value"/>
     <group name="valueSet" type="asnx:ValueSet"/>
     <group name="object" type="asnx:Object"/>
     <group name="objectSet" type="asnx:ObjectSet"/>
    </choice>
   </type>
  </namedType>
  <namedType name="ObjectSet">
   <type>
    <choice insertions="none">
     <attribute name="objectSet" identifier="objectSetRef"
                type="asnx:QName"/>
     <element name="objectSet" type="asnx:ElementFormObjectSet"/>
    </choice>
   </type>
  </namedType>
  <namedType name="ElementFormObjectSet">
   <type>
    <sequence insertions="hollow">
     <optional>
      <element name="annotation" type="asnx:Annotation"/>
     </optional>
     <group name="definition">
      <type>
       <choice insertions="none">
        <group name="reference" type="asnx:Reference"/>

Legg Experimental [Page 161] RFC 4912 Abstract Syntax Notation X July 2007

        <element name="expanded" type="asnx:ExpandedObjectSet"/>
        <group name="objectSetSpec" type="asnx:ObjectSetSpec"/>
        <element name="fromObjects"
                 type="asnx:InformationFromObjects"/>
       </choice>
      </type>
     </group>
    </sequence>
   </type>
  </namedType>
  <namedType name="ExpandedObjectSet">
   <type>
    <sequence>
     <optional>
      <attribute name="name" type="asnx:NCName"/>
     </optional>
     <optional>
      <element name="module" type="asnx:ReferencedModule"/>
     </optional>
     <group name="objectSet" type="asnx:ObjectSet"/>
    </sequence>
   </type>
  </namedType>
  <namedType name="ObjectSetSpec">
   <type>
    <constrained>
     <type>
      <sequence insertions="hollow">
       <optional>
        <group name="root" type="asnx:ObjectElementSetSpec"/>
       </optional>
       <optional>
        <element name="extension">
         <type>
          <sequence insertions="hollow">
           <optional>
            <group name="additions" type="asnx:ObjectElementSetSpec"/>
           </optional>
          </sequence>
         </type>
        </element>
       </optional>
      </sequence>
     </type>
     <union>
      <withComponents partial="true">

Legg Experimental [Page 162] RFC 4912 Abstract Syntax Notation X July 2007

       <group name="root" use="present"/>
      </withComponents>
      <withComponents partial="true">
       <element name="extension" use="present"/>
      </withComponents>
     </union>
    </constrained>
   </type>
  </namedType>
  <namedType name="ObjectElementSetSpec">
   <type>
    <constrained type="asnx:ElementSetSpec">
     <withComponents partial="true">
      <element name="literalValue" use="absent"/>
      <element name="value" use="absent"/>
      <element name="includes" use="absent"/>
      <element name="range" use="absent"/>
      <element name="size" use="absent"/>
      <element name="typeConstraint" use="absent"/>
      <element name="from" use="absent"/>
      <element name="withComponent" use="absent"/>
      <element name="withComponents" use="absent"/>
      <element name="pattern" use="absent"/>
      <element name="union">
       <withComponent>
        <includes type="asnx:ObjectElementSetSpec"/>
       </withComponent>
      </element>
      <element name="intersection">
       <withComponent>
        <includes type="asnx:ObjectElementSetSpec"/>
       </withComponent>
      </element>
      <element name="all">
       <withComponents partial="true">
        <group name="elements">
         <includes type="asnx:ObjectElementSetSpec"/>
        </group>
        <element name="except">
         <includes type="asnx:ObjectElementSetSpec"/>
        </element>
       </withComponents>
      </element>
     </withComponents>
    </constrained>
   </type>
  </namedType>

Legg Experimental [Page 163] RFC 4912 Abstract Syntax Notation X July 2007

  <namedType name="EncodingControlSections">
   <type>
    <sequenceOf minSize="1">
     <group name="section" type="asnx:EncodingControlSection"/>
    </sequenceOf>
   </type>
  </namedType>
  <namedType name="EncodingControlSection">
   <type>
    <choice insertions="singular">
     <element name="GSER" identifier="gser"
              type="asnx:GSER-EncodingInstructionAssignmentList"/>
     <element name="XER" identifier="xer"
              type="asnx:XER-EncodingInstructionAssignmentList"/>
     <!-- plus encoding control sections
          for other encoding rules in the future -->
    </choice>
   </type>
  </namedType>
  <element name="module" type="asnx:ModuleDefinition"/>
  <attribute name="literal" type="asnx:BOOLEAN"/>
 </asnx:module>

Author's Address

 Dr. Steven Legg
 eB2Bcom
 Suite 3, Woodhouse Corporate Centre
 935 Station Street
 Box Hill North, Victoria 3129
 AUSTRALIA
 Phone: +61 3 9896 7830
 Fax:   +61 3 9896 7801
 EMail: steven.legg@eb2bcom.com

Legg Experimental [Page 164] RFC 4912 Abstract Syntax Notation X July 2007

Full Copyright Statement

 Copyright (C) The IETF Trust (2007).
 This document is subject to the rights, licenses and restrictions
 contained in BCP 78, and except as set forth therein, the authors
 retain all their rights.
 This document and the information contained herein are provided on an
 "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
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 THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS
 OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
 THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
 WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

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 Intellectual Property Rights or other rights that might be claimed to
 pertain to the implementation or use of the technology described in
 this document or the extent to which any license under such rights
 might or might not be available; nor does it represent that it has
 made any independent effort to identify any such rights.  Information
 on the procedures with respect to rights in RFC documents can be
 found in BCP 78 and BCP 79.
 Copies of IPR disclosures made to the IETF Secretariat and any
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Acknowledgement

 Funding for the RFC Editor function is currently provided by the
 Internet Society.

Legg Experimental [Page 165]

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