[MS-XAML]:

Xaml Object Mapping Specification 2006

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[MS-XAML] v1.0
Xaml Object Mapping Specification 2006
Copyright 2008 Microsoft Corporation.
Release: June 2008
Contents
[MS-XAML]: .............................................................................................................................................1
Xaml Object Mapping Specification 2006 ...............................................................................................1
Contents ..................................................................................................................................................2
Preface ....................................................................................................................................................6
About This Specification..........................................................................................................................6
Language Notes .......................................................................................................................................6
Section 1. Overview .............................................................................................................................7
1.1 Xaml Vocabularies and the Xaml Schema Information Set..................................................... 7
1.2 Xaml Instances, Xaml Documents and the Xaml Information Set .......................................... 8
1.3 Well-Formed and Valid Xaml Information Sets ...................................................................... 8
1.4 The Structure of Information in Xaml ..................................................................................... 8
1.5 A Note on Notation ................................................................................................................. 9
Section 2. Information Set Type System ........................................................................................... 10
2.1 Text String ............................................................................................................................. 10
2.2 XamlName ............................................................................................................................. 10
2.3 Namespace Uri ...................................................................................................................... 11
2.4 Boolean ................................................................................................................................. 11
2.5 Allowed Location ................................................................................................................... 11
2.6 XML Namespace Mapping .................................................................................................... 11
2.7 Set ......................................................................................................................................... 11
2.8 Ordered Collection ................................................................................................................ 11
Section 3. Xaml Schema Information Set .......................................................................................... 13
3.1 Schema Information Item ..................................................................................................... 14
3.1.1. Constraints .................................................................................................................... 14
3.1.2. Notes (Non-Normative) ................................................................................................ 14
3.2 XamlType Information Item .................................................................................................. 15
3.2.1. Constraints .................................................................................................................... 17
3.2.2. Notes (Non-Normative) ................................................................................................ 18
3.3 XamlMember Information Item ............................................................................................ 18
3.3.1. Constraints .................................................................................................................... 19
3.3.2. Notes (Non-Normative) ................................................................................................ 20
3.4 Text Syntax Information Item ............................................................................................... 20
3.4.1. Constraints .................................................................................................................... 21
3.4.2. Notes (Non-Normative) ................................................................................................ 21
3.5 Value Syntax Information Item ............................................................................................. 21
3.5.1. Constraints .................................................................................................................... 22
3.6 Pattern Syntax Information Item .......................................................................................... 22
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3.6.1. Constraints .................................................................................................................... 22
3.7 Constructor Information Item .............................................................................................. 22
3.7.1. Constraints .................................................................................................................... 23
Section 4. Xaml Information Set ........................................................................................................ 24
4.1 Document Information Item ................................................................................................ 24
4.1.1. Constraints .................................................................................................................... 24
4.2 Object Node Information Item ............................................................................................. 25
4.2.1. Constraints .................................................................................................................... 26
4.2.2. Validity Constraints....................................................................................................... 26
4.2.3. Note (non-normative) .................................................................................................. 30
4.3 Member Node Information Item .......................................................................................... 30
4.3.1. Constraints .................................................................................................................... 30
4.3.2. Validity Constraints....................................................................................................... 32
4.3.3. Notes (Non-Normative) ................................................................................................ 35
4.4 Text Node Information Item ................................................................................................. 36
4.4.1. Constraints .................................................................................................................... 36
4.4.2. Notes (Non-Normative) ................................................................................................ 36
Section 5. Intrinsic Schema Information Items ................................................................................. 38
5.1 Intrinsic Schema Information Items ..................................................................................... 38
5.1.1. The x: Schema ............................................................................................................. 38
5.1.2. The XML Namespace Schema ....................................................................................... 38
5.2 Intrinsic XamlType Information Items .................................................................................. 39
5.2.1. x:ArrayExtension ........................................................................................................... 39
5.2.2. x:StaticExtension .......................................................................................................... 40
5.2.3. x:TypeExtension ............................................................................................................ 40
5.2.4. x:NullExtension ............................................................................................................. 40
5.2.5. x:Object......................................................................................................................... 41
5.2.6. x:String .......................................................................................................................... 41
5.2.7. x:Char ............................................................................................................................ 41
5.2.8. x:Single .......................................................................................................................... 41
5.2.9. x:Double ........................................................................................................................ 42
5.2.10. x:Byte ............................................................................................................................ 42
5.2.11. x:Int16 ........................................................................................................................... 42
5.2.12. x:Int32 ........................................................................................................................... 43
5.2.13. x:Int64 ........................................................................................................................... 43
5.2.14. x:Decimal ...................................................................................................................... 43
5.2.15. x:Uri .............................................................................................................................. 44
5.2.16. x:Timespan.................................................................................................................... 44
5.2.17. x:Boolean ...................................................................................................................... 44
5.2.18. x:Array .......................................................................................................................... 45
5.2.19. x:XamlType ................................................................................................................... 45
5.2.20. x:XamlEvent .................................................................................................................. 45
5.2.21. x:MarkupExtension ....................................................................................................... 46
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5.2.22. x:Code ........................................................................................................................... 46
5.2.23. x:XData .......................................................................................................................... 46
5.3 Intrinsic XamlMember Information Items ............................................................................ 46
5.3.1. x:Items ........................................................................................................................... 47
5.3.2. x:ConstructorArgs ......................................................................................................... 47
5.3.3. x:InitializationText ......................................................................................................... 47
5.3.4. x:Name Directive ........................................................................................................... 48
5.3.5. x:Key Directive............................................................................................................... 48
5.3.6. x:Uid Directive ............................................................................................................... 48
5.3.7. x:Class Directive ............................................................................................................ 49
5.3.8. x:Subclass Directive ....................................................................................................... 49
5.3.9. x:ClassModifier Directive .............................................................................................. 49
5.3.10. x:FieldModifier Directive ............................................................................................... 49
5.3.11. x:TypeArguments Directive ........................................................................................... 50
5.3.12. x:DirectiveChildren ........................................................................................................ 50
5.3.13. xml:lang Directive ......................................................................................................... 50
5.3.14. xml:space Directive ....................................................................................................... 50
5.3.15. xml:base Directive ......................................................................................................... 51
5.3.16. ArrayExtension.Items .................................................................................................... 51
5.3.17. ArrayExtension.Type ..................................................................................................... 51
5.3.18. StaticExtension.Member ............................................................................................... 51
5.3.19. TypeExtension.Type ...................................................................................................... 52
5.3.20. TypeExtension.TypeName ............................................................................................ 52
5.4 Intrinsic Text Syntax Information Items ................................................................................ 52
5.4.1. x:Char Text Syntax ......................................................................................................... 53
5.4.2. x:Single Text Syntax ....................................................................................................... 53
5.4.3. x:Double Text Syntax ..................................................................................................... 53
5.4.4. x:Byte Text Syntax ......................................................................................................... 54
5.4.5. x:Int16 Text Syntax ........................................................................................................ 54
5.4.6. x:Int32 Text Syntax ........................................................................................................ 54
5.4.7. x:Int64 Text Syntax ........................................................................................................ 54
5.4.8. x:Decimal Text Syntax ................................................................................................... 55
5.4.9. x:Uri Text Syntax ........................................................................................................... 55
5.4.10. x:Timespan Text Syntax ................................................................................................. 55
5.4.11. x:Boolean Text Syntax ................................................................................................... 55
5.4.12. x:XamlType Text Syntax ................................................................................................ 56
5.4.13. xml:space Text Syntax ................................................................................................... 56
5.4.14. x:XamlEvent Text Syntax ............................................................................................... 56
5.5 Intrinsic Constructor Information Items ............................................................................... 56
5.5.1. Static Extension String Constructor .............................................................................. 57
5.5.2. Type Extension String Constructor ................................................................................ 57
Section 6. Creating a Xaml Information Set from XML ..................................................................... 58
6.1 Unavailability of Xaml Schemas ............................................................................................ 58
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6.2 Processing Errors .................................................................................................................. 58
6.3 Markup Compatibility ........................................................................................................... 58
6.3.1. Raw Mode ..................................................................................................................... 59
6.3.2. Preprocessed Mode ...................................................................................................... 59
6.3.3. Subsumption Behavior ................................................................................................. 59
6.4 XML Information Set References .......................................................................................... 59
6.5 Definitions ............................................................................................................................ 59
6.5.1. DottedXamlName ......................................................................................................... 60
6.5.2. Collapsible Whitespace Characters .............................................................................. 60
6.5.3. Linefeed Collapsing Characters .................................................................................... 60
6.5.4. Authoritative Schema ................................................................................................... 61
6.6 Document Processing Rules ................................................................................................. 61
6.6.1. XML:document Processing ........................................................................................... 62
6.6.2. Object Node Creation from an XML:element ............................................................... 63
6.6.3. Member Node Creation from an XML:attribute .......................................................... 68
6.6.4. Value Creation from Attribute Text .............................................................................. 71
6.6.5. Member Node Creation from an XML:element ........................................................... 72
6.6.6. Member Node Creation from Content ......................................................................... 74
6.6.7. Object Node Creation from a Markup Extension in an Attribute ................................. 76
6.6.8. Member Lookup ........................................................................................................... 82
6.6.9. Xml Namespace Mapping Conversion .......................................................................... 82
Appendix A: References .................................................................................................................... 84
Appendix B: Microsoft .NET Framework Behavior ........................................................................... 86


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[MS-XAML] v1.0
Xaml Object Mapping Specification 2006
Copyright 2008 Microsoft Corporation.
Release: June 2008
Preface
About This Specification
Xaml, the eXtensible Application Markup Language, is a system for representing structured
information. This specification defines three aspects of Xaml:
The Xaml Schema Information Set a model for defining a particular Xaml vocabulary.
The Xaml Information Set a model for describing the information in a Xaml instance.
The process for converting an XML [XML] document into the corresponding Xaml
Information Set, as directed by one or more Xaml Schema Information Sets.
This specification does not define any particular Xaml vocabulary.
Language Notes
In this specification, the words that are used to define the significance of each particular
requirement are capitalized. These words are used in accordance with their definitions in RFC 2119
[RFC 2119] and their meaning is reproduced here for convenience:
MUST. This word, or the adjective REQUIRED, means that the item is an absolute
requirement of the specification.
SHOULD. This word, or the adjective RECOMMENDED, means that there may exist valid
reasons in particular circumstances to ignore this item, but the full implications should be
understood and the case carefully weighed before choosing a different course.
MAY. This word, or the adjective OPTIONAL, means that this item is truly optional. For
example, one implementation may choose to include the item because a particular
marketplace or scenario requires it or because it enhances the product. Another
implementation may omit the same item.


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Section 1. Overview
Xaml, the eXtensible Application Markup Language, is a system for representing structured
information. This specification defines two abstract information models: the Xaml Schema
Information Set model, and the Xaml Information Set model. The Xaml Information Set (Xaml
Infoset for short) defines the structure of information that a Xaml instance can represent. The Xaml
Schema Information Set allows specific Xaml vocabularies to be defined. This specification also
defines a set of rules for transforming an XML document into a Xaml Information Set.
XML is a common format for Xaml. (The term Xaml Document refers to an XML document that
represents a Xaml Information Set.) But while this specification does not define any other
representations, any physical representation may be used as long as it can represent the
information in the Xaml Information Set.
This first section of the specification describes the roles of the information sets, how they relate to
applications that use Xaml, and how the transformation rules come into play.
1.1 Xaml Vocabularies and the Xaml Schema Information Set
This specification does not mandate any particular application or interpretation of a Xaml
Document. Each individual application of Xaml will define its own Xaml Vocabulary. For example,
Xaml could be used to define the structure of a graphical user interface, or it could be used to
represent a list of pieces of music. This specification does not define any such application-specific
vocabularies. This specification provides the information to enable such vocabularies to be defined.
A particular Xaml vocabulary is defined as a Xaml Schema. A schema defines the object types that
may be used in a Xaml instance, determining the members and content each type supports.
(Individual applications will likely go further, assigning meanings to element types. However, that is
beyond the scope of a Xaml Schema.) Furthermore, some schema features are advisory a schema
may contain information which is not strictly required to process a Xaml Document, but which may
be useful to tools. (For example, the information may enable compilers to provide better warnings,
or for editors to offer better discoverability.)
A Xaml Schema is always associated with a particular namespace URI. XML representations of Xaml
indicate their vocabulary through XML namespaces the namespace URI of an element or attribute
indicates the Xaml Schema to which that node belongs.
This specification does not define a Xaml Schema file format. Instead, this specification defines an
abstract data model for schemas, the Xaml Schema Information Set. This specifies the information
required to form a complete schema. It is defined in Section 3, Xaml Schema Information Set.
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1.2 Xaml Instances, Xaml Documents and the Xaml Information Set
A Xaml Instance is a structured set of information, made up of the elements described in Section 4,
Xaml Information Set. The term does not mandate any particular representation. The term Xaml
Document means an XML document that represents a Xaml Instance. The process for converting
the XML in a Xaml Document into the Xaml Instance it represents is described in Section 6, Creating
a Xaml Information Set from XML.
The conversion process is defined in terms of the XML Information Set [XML Infoset], so the input
XML document does not need to be a text stream formatted as required by the XML specification.
Any representation may be used, as long as it can be mapped to the logical XML Information Set
structure. For example, a Xaml Document could use a binary format, or it might be held in memory
as a set of objects or data structures. As with Xaml Schemas, this specification is not concerned with
the physical representation of a Xaml Document, only the logical structure.
1.3 Well-Formed and Valid Xaml Information Sets
This specification defines two characteristics that a Xaml Information Set may possess. It may be a
well-formed Xaml Information Set. And it may be a valid Xaml Information Set.
A Xaml Information Set is well-formed if it conforms to all of the rules for well-formedness in Section
4, Xaml Information Set.
A Xaml Information Set is valid with respect to one or more schemas if it conforms to all of the rules
for validity in Section 4, Xaml Information Set.
A Xaml Document, i.e. an XML document representing a Xaml Instance, is valid with respect to a set
of schemas if it can be successfully converted into a Xaml Infoset using the process defined in
Section 6, and the resulting Xaml Infoset is valid with respect to those schemas.
1.4 The Structure of Information in Xaml
There are obvious parallels between the world of XML and Xaml. Each have schemas, documents
and concepts of being well-formed and valid. The main difference is that the structure of the Xaml
Information Set is more specialized than the XML Information Set. In particular, although there is no
requirement that a Xaml instance be represented as objects in an object-oriented programming
system, the Xaml Information Set has been designed to make such a mapping straightforward. Xaml
Schemas are correspondingly specialized.
The structure of the information in a Xaml Information Set is described formally in Section 3, Xaml
Schema Information Set, but as an aid to understanding, there follows a short, informal, non-
normative description of the structure.
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Information in a Xaml Instance is in one of three forms: objects, members, or text. The root of a
Xaml Instance is an object. Objects can have members; an objects members are unordered.
Members have values, which consist either of objects or text. Some members may have multiple
values (forming an ordered sequence); in such cases, a single members values may comprise a
mixture of objects and text. Figure 1 shows an example XML representation of Xaml, and an
illustration of the structure of the Xaml Infoset the XML represents.

Figure 1: Structure of Xaml Information (non-normative)
Some non-normative sections of this specification use terminology common in object oriented
programming systems. An instance of a type means an object of that type. Construction refers to
the act of creating an object.
1.5 A Note on Notation
When referring to Information Set properties (whether Xaml or XML), this specification uses
bracketed notation. For example if elem refers to an XML element in an XML information set,
elem[attributes] refers to the [attributes] property of that element.

<MyElem Width="42"
Quality="High">

<MyElem.Bar>
<Child Less="More" />
</MyElem.Bar>

</MyElem>
Object: MyElem
Member: MyElem.Width
Member: MyElem.Quality
Text: 42
Text: High
Member: MyElem.Bar
Object: Child
Member: Child.Less
Text: More
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Section 2. Information Set Type System
The Xaml Schema Information Set and the Xaml Information Set each define a data model. The
models define various Information Item types. For example, the Xaml Schema Information Set
defines a Schema Information Item (3.1).
Information Items have various properties, each of which has a type. In some cases, the type is
another Information Item defined elsewhere in the data model. For example, the XamlMember
Information Item (3.3) in the Xaml Schema Information Set has a [value type] property, and its type
is another part of the model: a XamlType Information Item (3.2). However, these data models are
not defined entirely in terms of themselves. For example, a XamlType Information Item has a [name]
property whose type is XamlName. The following sections define the types such as these that are
used in the information sets in this specification.
2.1 Text String
An ordered sequence of Unicode [Unicode] characters.
2.2 XamlName
A XamlName is a Text String that conforms to the following grammar (using the syntax defined in
RFC4234 [ABNF]):
XamlName = NameStartChar *(NameChar)
NameStartChar = UnicodeLu / UnicodeLl / UnicodeLo
/ UnicodeLt / UnicodeNl / "_"
NameChar = NameStartChar / UnicodeNd / UnicodeMn
/ UnicodeMc / UnicodeLm
This assumes the following general category values as defined in the Unicode Character Database
[Unicode]:
Table 1: Unicode Category Abbreviations
Abbreviation Description
UnicodeLu Letter, Uppercase
UnicodeLl Letter, Lowercase
UnicodeLt Letter, Titlecase
UnicodeLm Letter, Modifier
UnicodeLo Letter, Other
UnicodeMn Mark, Non-Spacing
UnicodeMc Mark, Spacing Combining
UnicodeNd Number, Decimal
UnicodeNl Number, Letter

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2.3 Namespace Uri
A Namespace Uri is a sequence of characters identifying an XML namespace. Implementations that
process Xaml MUST accept any namespace name (as defined in section 2 of [XML Namespaces]) as
a Namespace Uri. Implementations MAY tolerate as identifiers sequences of Unicode characters
which are not valid namespace names.
2.4 Boolean
A truth value: either True or False.
2.5 Allowed Location
A value of this type represents an allowed location for a member in an XML representation some
members (e.g., the xml:lang Directive defined in 5.3.13) may only be specified as attributes in XML,
and not as member elements; some (e.g. the x:Items member defined in 5.3.1) may not appear in
XML at all, and are only used in a Xaml Information Set. Values of this type are one of: Any,
AttributeOnly, or None.
2.6 XML Namespace Mapping
A value of this type represents an XML namespace prefix and the corresponding XML namespace
URI. It has two properties: [prefix] of type Text String, and [uri] of type Namespace Uri.
2.7 Set
Some properties have a type defined as a Set of some type, or a list of types. For example,
XamlType Information Item (3.2) has a [types assignable to] property whose type is Set of XamlType
Information Items. Such property may contain any number of values of the type or types in
question. Order is not significant in a set. Sets do not contain duplicates any given value is either in
a set or it is not. Sets may be empty.
2.8 Ordered Collection
Some properties have a type defined as an Ordered Collection of some type, or a list of types. For
example, Member Node Information Item (4.3) has a [values] property, whose type is defined as
Ordered collection of information items; each item may be either an Object Node Information Item,
or a Text Node Information Item. Such properties may contain any number of values of the type or
types in question. The values are strictly ordered. Ordered collections may contain duplicates, e.g.
the second and fourth item in an ordered collection may be the same value. An ordered collection
may be empty.


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[MS-XAML] v1.0
Xaml Object Mapping Specification 2006
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Release: June 2008
Section 3. Xaml Schema Information Set
A Xaml Schema is an abstract definition of a set of Xaml Instances. A Xaml Infoset is said to be an
instance of a Xaml Schema if it conforms to all of the rules for well-formedness and validity in
Section 4, Xaml Information Set.
This specification does not mandate a representation or format for a Xaml Schema. Instead, it
defines an abstract data model called the Xaml Schema Information Set, or Schema Infoset for
short, which defines the elements that make up a Xaml Schema.
A Xaml Schema Information Set can contain five kinds of items. These are listed in Table 2.
Table 2: Xaml Schema Information Set Item Kinds
Item Kind Purpose (non-normative)
Schema Information Item Identifies a schema, and defines which information items
constitute that schemas definition.
XamlType Information Item Describes a type of element that instances of this schema
may contain.
XamlMember Information Item Describes a member that may be applied to elements in
instances of this schema.
Text Syntax Information Item Describes the valid textual representations of the values of a
particular member or type.
Constructor Information Item Describes the available constructor forms for a type.
The information items that make up the Xaml Schema Information Set have identity. For example,
given two XamlMember Information Items, it is meaningful to ask if their [value type] properties
each refer to the same XamlType Information Item (or more informally, whether the two members
have the same type). Since this specification does not mandate any particular representation for
schema infosets, implementations are free to represent this in any way. For example, a
programming system might choose to represent item identity through object identity where such a
concept is supported; a serialized representation might choose to add identifiers that do not
correspond directly to infoset properties purely to handle item identity.
The following sections describe the data properties that make up each of the information item
types. These sections also define constraints a Xaml Schema must meet.
In some cases, notes are provided to describe the purpose of certain data properties in more detail.
This is done in situations where the normative interpretation of these properties is defined in other
sections, but where the intended meaning of the properties would be hard to infer. These notes are
provided purely as an aid to understanding, and are marked as non-normative to indicate that they
does not constitute a formal part of the Xaml Schema Infoset specification. The Purpose column of
each table defining an information item has a similar role, and is also non-normative.
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3.1 Schema Information Item
Each Xaml Schema MUST have one Schema Information Item. The Schema Information Item is the
root of a schemas definition, defining which other items belong to this schema.
Table 3: Schema Information Item Properties
Name Type Purpose (non-normative)
[target namespace] Namespace Uri The target XML namespace for this schema.
[types] Set of XamlType
Information Items
The object types that instances of this
schema may contain.
[assignable types] Set of XamlType
Information Items
Types that are not used directly as values in
instances of this schema, but which are used
by XamlMember Information Items for
assignability purposes.
[directives] Set of XamlMember
Information Items
The directive attributes that may be applied
to objects in instances of this schema.
[compatible with schemas] Set of Schema
Information Items
The schemas with which this schema is
considered compatible.

3.1.1. Constraints
A Xaml Schema Information Sets Schema Information Item MUST conform to the rules defined in
this section.
3.1.1.1. Information Set Properties Must Be of Correct Type
Each property of a Schema Information Item MUST have a value of the type specified for that
property in Table 3.
3.1.1.2. Members in [directives] Must Be Directives
For each XamlMember Information Item d in [directives], d[is directive] MUST be True.
3.1.1.3. Type Names Must Be Unique
For each XamlType Information Item t in [types] the value of t[name] MUST be different from the
[name] of any other XamlType Information Item in [types].
3.1.1.4. Directive Names Must be Unique
For each XamlMember Information Item d in [directives] the value of d[name] MUST be different
from the [name] of any other XamlMember Information Item in [directives].
3.1.2. Notes (Non-Normative)
The [compatible with schemas] property addresses two scenarios. It is used when new versions of a
vocabulary are developed that are compatible with older versions. It is also used to handle cases
where multiple distinct namespaces may identify structurally identical schemas.
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The types in [types] can be used for assignability purposes as well as the types in [assignable types].
The significance of [assignable types] is that types in this property do not support the full range of
features that types in [types] do.
3.2 XamlType Information Item
A XamlType Information Item defines a data type. For example, an Object Node Information Item
(4.2) has a [type] property that refers to a XamlType Information Item.
Table 4: XamlType Information Item Properties
Name Type Purpose (non-normative)
[name] XamlName The name that represents this type. Case is
significant.
[types assignable to] Set of XamlType
Information Items
The types to which instances of this type are
considered assignable.
[is default
constructible]
Boolean When True, this type may always be used as the
type for an object node. When False, constraints
apply, which are described later in this
specification.
[is nullable] Boolean True if members of this type may have a Null
value.
[text syntax] Null, or Text Syntax
Information Item
The text syntax that defines how instances of
this type can be represented as text.
[members] Set of XamlMember
Information Items
The members available on this type.
[content property] Null, or a
XamlMember
Information Item
The member to which content of an element of
this type can be assigned. (Allows XML
representations to omit the member element.)
[dictionary key
property]
Null, or a
XamlMember
Information Item
The member that acts as the key if an element
of this type is added to a dictionary without a
key being specified explicitly. The designated
member is effectively an alias for the x:Key
directive (5.3.5).
[name property] Null, or a
XamlMember
Information Item
The member that, if set, holds the name of an
element of this type. The designated member is
effectively an alias for the x:Name Directive
(5.3.4).
[xml lang property] Null, or a
XamlMember
Information Item
The member that holds the value of the
xml:lang attribute (when present) the
designated member is effectively an alias for the
xml:lang Directive (5.3.13).
[trim surrounding
whitespace]
Boolean True if whitespace immediately before and after
elements of this type in an XML representation
should be removed.
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[is whitespace
significant collection]
Boolean True if, when a Xaml processor reads an XML
representation of an element of this type,
whitespace content should not be collapsed.
[is list] Boolean True if elements of this type contain an ordered
sequence of items.
[is dictionary] Boolean True if elements of this type contain a set of
items, each identified by a key.
[allowed types] Set of XamlType
Information Items
The types that can be added as items inside a
list or dictionary. (Only used if [is list] or [is
dictionary] is True.)
[allowed key types] Set of XamlType
Information Items
The types that can be used as keys. (Only used if
[is dictionary] is True.)
[is xdata] Boolean True if elements of this type contain literal XML
data.
[is name scope] Boolean Used to determine the scope in which values of
the x:Name Directive (5.3.4) must be unique.
[constructors] Set of Constructor
Information Items
The constructors that can be used to create
instances of this type.
[return value type] Null, or a XamlType
Information Item
The type of value provided by this type. (Only
used for markup extensions see the
x:MarkupExtension type (5.2.21).)

The [types assignable to] property contains the complete set of types from this schema to which
instances of this type is assignable. If a vocabulary wishes to provide common object-oriented
semantics, such as having a type be assignable to all the types to which its base class is assignable, it
must make that explicit. However, there is an additional complexity regarding schemas that list
other schemas in their [compatible with schemas]. Types do not include types from the schemas
with which they are compatible with their [types assignable to]. Instead, this specification presumes
that equivalently named types in compatible schemas are compatible. To simplify the validity checks
that presume this, the following functions are defined:
1, 2
1[name] = 2[name]
(1 [ Schema Information Item) [types] 1
(2 [ Schema Information Item) [types] 2
((1 = 2)

1 2[compatible with schemas]

(2 1[compatible with schemas]) )))

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, ,
( | ( [types assignable to]) (, ))

Informally, a type tFrom is assignable to a type tTo if either tFrom and tTo are compatible, or if
tFrom[types assignable to] contains a type which is compatible with tTo; types are compatible with
types that have the same name and compatible schemas.
3.2.1. Constraints
The XamlType Information Items in a Xaml Schema Information Set MUST conform to the rules
defined in this section.
3.2.1.1. Information Set Properties Must Be of Correct Type
Each property of a XamlType Information Item MUST have a value of the type specified for that
property in Table 4.
3.2.1.2. Content Member Must Be Available
If a types [content property] is not Null, that types [members] MUST contain the member in
[content property].
3.2.1.3. Name Member Must Be Available
If a types [name property] is not Null, that types [members] MUST contain the member in [name
property].
3.2.1.4. Content Member Mutually Exclusive with List and Dictionary
If [content property] is not Null, [is list] and [is dictionary] MUST both be False.
3.2.1.5. List and Dictionary Mutually Exclusive
If [is list] is True, [is dictionary] MUST be False (from which the converse follows: if [is dictionary] is
True, [is list] MUST be False.)
3.2.1.6. Allowed Types Only Used on Lists and Dictionaries
[allowed types] MUST be empty unless either [is list] or [is dictionary] is True.
3.2.1.7. Allowed Key Types Only Used on Lists and Dictionaries
[allowed key types] MUST be empty unless [is dictionary] is True.
3.2.1.8. Return Value Type Required on Markup Extension
If [types assignable to] contains the intrinsic x:MarkupExtension type (5.2.21), [return value type]
MUST NOT be Null.
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3.2.1.9. Return Value Type Only Used on Markup Extension
If [types assignable to] does not contain the intrinsic x:MarkupExtension type (5.2.21), [return value
type] MUST be Null.
3.2.1.10. Only Markup Extensions Can Have Constructors
If [types assignable to] does not contain the intrinsic x:MarkupExtension type (5.2.21), [constructors]
MUST be empty.
3.2.1.11. No Two Constructors May Have the Same Number of Arguments
For each Constructor Information Item ctor in [constructors], [constructors] MUST NOT contain any
other Constructor Information Items that have the same number of items in their [arguments] as
there are in ctor[arguments].
3.2.2. Notes (Non-Normative)
Both [members] and [types assignable to] are comprehensive within a schema, i.e., types do not
automatically inherit everything that types in [types assignable to] have. For example suppose type
B has member BP, and a type D has a [types assignable to] containing B, if D wishes to make BP
available, D[members] must contain BP. The reason for this is not to force Xaml vocabularies to use
normal inheritance rules. Vocabularies that wish to offer a typical object-oriented style of
inheritance are free to do so, they must simply be explicit.
However, type assignability is honored in Xaml Instances. For example, consider [allowed types].
Items in a list or dictionary may also be of types that are assignable to types in [allowed types], as
determined by each item types [types assignable to] property. Likewise, for [allowed key types], key
values may also be of types that are assignable to types in this list.
In short, Xaml Schemas are required to be explicit; validation of Xaml Instances does whatever the
schema says.
3.3 XamlMember Information Item
A XamlMember Information Item provides information about a member. Members are either
defined by a particular XamlType Information Item, or they are directives.
Table 5: XamlMember Information Item Properties
Name Type Purpose (non-normative)
[name] XamlName The name of the member.
[owner type] Null or XamlType
Information Item
The type that defines this member, or Null if [is
directive] is True.
[value type] XamlType Information
Item
The type that values for this member must be
assignable to.
[text syntax] Null, or Text Syntax A member-specific text syntax that defines how this
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Information Item member can be represented as text. (If present, this
takes precedence over [value type][text syntax].)
[is read only] Boolean True if the member cannot be set. (Only used for lists
and dictionaries.)
[is static] Boolean True if the member is associated directly with the
defining type, and not with any particular element.
[is attachable] Boolean True if this member may be applied to types other
than those compatible with the owner type.
[target type] Null, or XamlType
Information Item
The member may be attached to types compatible
with this type. (Only used for attachable members.)
[allowed location] Allowed Location Indicates how the member may be represented in
XML.
[is event] Boolean True if this member is used to define a response to
some event such as user input. (The interpretation of
event members is determined by individual Xaml
processors.)
[is directive] Boolean True if this is a directive.

3.3.1. Constraints
The XamlMember Information Items in a Xaml Schema Information Set MUST conform to the rules
defined in this section.
3.3.1.1. Information Set Properties Must Be of Correct Type
Each property of a XamlMember Information Item MUST have a value of the type specified for that
property in Table 5.
3.3.1.2. Member names must be unique
If [is directive] is False, the value of [name] MUST be different from the [name] of any other
XamlMember Information Item in [owner type][members].
3.3.1.3. Member Kind
At most one of [is attachable], [is event], and [is directive] can be True.
3.3.1.4. Must Have Owner Type or be Directive
If [is directive] is False, [owner type] MUST NOT be Null. If [is directive] is True, [owner type] MUST
be Null.
3.3.1.5. Owner Type Must Own Member
If [owner type] is not Null, this XamlMember Information Item MUST be in [owner type][members].
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3.3.1.6. Only List, Dictionary, or Static Members may be Read-only
If neither [value type][is list] nor [value type][is dictionary], nor [is static] is True, [is read only] MUST
be False.
3.3.1.7. Properties Required by Attachable Members
If [is attachable] is True, [target type] MUST NOT be Null.
3.3.1.8. Properties Unique to Attachable Members
If [is attachable] is False, [target type] MUST be Null.
3.3.1.9. Event Type Must Be XamlEvent
If [is event] is True, [value type] MUST be the intrinsic x:XamlEvent (5.2.20).
3.3.1.10. Properties Not Supported By Directives
If [is directive] is True, [owner type] MUST be Null.
3.3.2. Notes (Non-Normative)
A member whose [value type] is a list or dictionary can be read-only, because it is still possible to
modify the contents of the list or dictionary, even when the member that holds it cannot be
changed. In this case, being read-only merely prevents us from supplying our own list or dictionary.
Members for which [is attachable] is True can be applied in a non-attached manner on instances of
the type that defines the member, as long as the member target is compatible with the members
[target type]. E.g., if a type Canvas defines an attachable Canvas.Left member, that member can be
used in a non-attached fashion on a Canvas.
Directives are similar to members in the XML representation, they are set on object nodes using
the same syntax as a member, and in the Xaml Information Set, directives are represented as
member nodes. However, unlike normal members, a directive is not owned by any particular type.
Directives are typically associated with special behaviors in the Xaml handling. For example, this
specification defines some intrinsic directives in Section 5, Intrinsic Schema Information Items,
such as x:Key (5.3.5), which determines how dictionary items are handled.
3.4 Text Syntax Information Item
A Text Syntax Information Item describes the way in which the values for a particular type or
member can be represented in a Xaml Instance.
Table 6: Text Syntax Information Item Properties
Name Type Purpose (non-normative)
[values] Set of Value Syntax
Information Items
Fixed textual values that are known to be valid.
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[patterns] Set of Pattern Syntax
Information Items
Pattern-based expression of valid values.

3.4.1. Constraints
The Text Syntax Information Items in a Xaml Schema Information Set MUST conform to the rules
defined in this section.
3.4.1.1. Information Set Properties Must Be of Correct Type
Each property of a Text Syntax Information Item MUST have a value of the type specified for that
property in Table 6.
3.4.2. Notes (Non-Normative)
Members and types can have Text Syntax Information Items associated with them. The [values]
property contains a list of literal values the member may use. This could be used for a member that
corresponded to an enumerated type in a programming system [values] would contain one string
for each enumeration member.
The [patterns] property is used when the set of valid values is either not closed, or would be too
large to enumerate. For example, it would not be practical to describe the valid values for a numeric
field by putting every possible number representation into [values]. Instead, [patterns] would
capture the valid values.
A Text Syntax Information Item is may contain multiple [values] and [patterns]. A text value is
considered a match if it matches at least one value or pattern. (All of this is formalized in the Section
4, Xaml Information Set.)
3.5 Value Syntax Information Item
A Value Syntax Information Item describes a possible value. All members of the [values] collection in
a Text Syntax Information Item are Value Syntax Information Items.
Table 7: Value Syntax Information Item Properties
Name Type Purpose (non-normative)
[text] Text String Fixed textual value that is known to be valid.
[trim
whitespace]
Boolean True if whitespace before and after the value
can be ignored.
[is case
sensitive]
Boolean True if the value must match exactly, false if the
value may be lower case or capitals.

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3.5.1. Constraints
The Text Syntax Information Items in a Xaml Schema Information Set MUST conform to the rules
defined in this section.
3.5.1.1. Information Set Properties Must Be of Correct Type
Each property of a Text Syntax Information Item MUST have a value of the type specified for that
property in Table 7.
3.6 Pattern Syntax Information Item
Pattern Syntax Information Item
Table 8: Pattern Syntax Information Item Properties
Name Type Purpose (non-normative)
[pattern] Text String Pattern-based expression of valid values.
[trim
whitespace]
Boolean True if whitespace before and after the value
can be ignored.
[is case
sensitive]
Boolean True if the value must match exactly, false if the
value may be lower case or capitals.
The string in [pattern] is a regular expression. Xaml Schema Infoset regular expressions use the same
formulation as those in XML Schema Definitions. See Appendix F of Part 2 of the XML Schema
specification [XML Schema Part 2].
3.6.1. Constraints
The Pattern Syntax Information Items in a Xaml Schema Information Set MUST conform to the rules
defined in this section.
3.6.1.1. Information Set Properties Must Be of Correct Type
Each property of a Pattern Syntax Information Item MUST have a value of the type specified for that
property in Table 8.
3.7 Constructor Information Item
A Constructor Information Item defines a parameter list that can be used to construct a particular
type.
Table 9: Constructor Information Item Properties
Name Type Purpose (non-normative)
[arguments] Ordered Collection of
XamlType Information
Items
The types of the parameters for this constructor.

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3.7.1. Constraints
The Constructor Information Items in a Xaml Schema Information Set MUST conform to the rules
defined in this section.
3.7.1.1. Information Set Properties Must Be of Correct Type
Each property of a Constructor Information Item MUST have a value of the type specified for that
property in Table 9.

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Section 4. Xaml Information Set
A Xaml Information Set represents the information contained in a Xaml Instance. A Xaml
Information Set can contain four kinds of items. These are listed in Table 10.
Table 10: Xaml Information Set Item Kinds
Item Kind Purpose (non-normative)
Document Information Item Represents a Xaml Instance.
Object Node Information Item Describes an object in the Xaml Instance.
Member Node Information Item Describes a member that has been set on a particular object in
the Xaml Instance.
Text Node Information Item Describes textual or whitespace content in the Xaml Instance.
The following sections describe the data properties that make up each of the information item
types. These sections also define constraints that all Xaml Instances are required to meet, and
further constraints that must be met for a Xaml Instance to be considered valid.
In some cases, notes are provided to describe the purpose of certain data properties in more detail.
This is done in situations where the normative interpretation of these properties is defined in other
sections, but where the intended meaning of the properties would be hard to infer. These notes are
provided purely as an aid to understanding, and are marked as non-normative to indicate that they
do not constitute a formal part of the Xaml infoset specification. The Purpose column of each table
defining an information item serves a similar role, and is also non-normative.
Note that many of the properties in the Xaml Information Set information items refer to information
items from the Xaml Schema Information Set.
4.1 Document Information Item
Each Xaml Instance has exactly one Document Information Item. It represents the document, and
provides access to the documents root.
Table 11: Document Information Item Properties
Name Type Purpose (non-normative)
[document object] Object Node Information
Item
The root object of the Xaml Instance.

4.1.1. Constraints
A well-formed Xaml Information Set MUST conform to the rules defined in this section.
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4.1.1.1. Information Set Properties Must Be of Correct Type
Each property of a Document Information Item MUST have a value of the type specified for that
property in Table 11.

4.1.1.2. Xaml Must Have Tree Structure
Consider a Xaml Information Set as a directed graph, where Object Node Information Items form
nodes, and edges are described by the Member Node Information Items in each Object Node
Information Items [member nodes]. This graph MUST NOT contain cycles. Furthermore, any single
Object Node Information Item MUST NOT be referred to by more than one Member Node
Information Item.
4.2 Object Node Information Item
Object nodes are one of the three main forms of information in a Xaml Information Set (the others
being member nodes and text nodes). Each object node is represented by an Object Node
Information Item.
Table 12: Object Node Information Item Properties
Name Type Purpose (non-normative)
[type] XamlType Information Item Schema-defined type of this object.
[member nodes] Set of Member Node
Information Items
The members that have been set on this object.
[parent member] Null, or Member Node
Information Item
The member node for which this object is a
value.
[is retrieved] Boolean True if this object node does not represent a
new object to be created instead, the
members in [member nodes] are to be set on an
existing object instance
[xml namespace
mappings]
Set of XML Namespace
Mappings
The XML namespace mappings in effect at this
element.
Some of the constraints that follow refer to a root node. This is the node in the Document
Information Items [document object] property. Although Object Node Information Items do not
contain a reference back to their containing Document Information Item, the root node can still be
located with the following process:
1. Let current node be the node for which the root is to be found.
2. If the [parent member] of current node is Null, the current node is the root node; if not,
continue to the next step.
3. Take the [parent member][parent object] of the current node, make that the new current
node, and then repeat from step 2.
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4.2.1. Constraints
The Object Node Information Items in a well-formed Xaml Information Set MUST conform to the
rules defined in this section.
4.2.1.1. Information Set Properties Must Be of Correct Type
Each property of an Object Node Information Item MUST have a value of the type specified for that
property in Table 12.
4.2.1.2. Events Not Allowed Unless Root Has x:Class
[member nodes] MUST NOT contain any Member Node Information Items (4.3) whose [is event] is
True unless the root nodes [member nodes] contains a Member Node Information Item whose
[member] is the x:Class directive XamlMember Information Item (5.3.7).
4.2.1.3. Cannot Have Multiple Member Nodes with Same Member
The Member Node Information Items in [member nodes] MUST all have different [member] items.
4.2.1.4. Parent Must Contain This Node
This Object Node Information Item MUST be in [parent member][values].
4.2.2. Validity Constraints
The Object Node Information Items in a valid Xaml Information Set MUST conform to the rules
defined in this section.
4.2.2.1. Cannot Set Both x:Name and Name Member
If [member nodes] contains a Member Node Information Item whose [member] is the intrinsic
x:Name Directive (5.3.4), [member nodes] MUST NOT also contain an item whose [member] is this
nodes [type][name property].
4.2.2.2. Cannot Set Both xml:lang and Language Member
If [member nodes] contains an item whose [member] is the intrinsic xml:lang Directive (5.3.13),
[member nodes] MUST NOT also contain an item whose [member] is this nodes [type][xml lang
property].
4.2.2.3. Types without Default Constructor Require Constructor Parameters
If the nodes [type][is default constructible] is False, the nodes [member nodes] MUST contain an
item whose [member] is the intrinsic x:ConstructorArgs (5.3.2).
4.2.2.4. Constructor Parameters Must Match Constructor Info
If the nodes [member nodes] contain an item whose [member] is the intrinsic x:ConstructorArgs
(5.3.2) call that item constructorArgs. The nodes [type][constructors] MUST contain a Constructor
Information Item for which the number of XamlType Information Items in
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constructorInfo[arguments] is the same as the number of items in constructorArgs[values]. Call that
item constructorInfo.
For each XamlType Information Item argType in constructorInfo[arguments], and for the item
argValue at the same offset into the constructorArgs[values] sequence, the following apply:
If argValue is a Text Node Information Item, one of the following MUST be true:
o argType is the intrinsic x:String (5.2.6).
o argType[text syntax] is non-Null.
Otherwise, argValue is an Object Node Information Item, and one of the following MUST be
true:
o isAssignableTo(argValue[type], argType) is True.
o argValue[type][types assignable to] contains the x:MarkupExtension (5.2.21)
intrinsic type, and isAssignableTo(argValue[type][return value type], argType) is
True.
4.2.2.5. Initialization Text Must Match Text Syntax
If the nodes [member nodes] contain an item whose [member] is the intrinsic x:InitializationText
(5.3.3), that items [values] MUST contain a single Text Node Information Item. Let initializationText
be the [text] of that text node.
Let textSyntax be a Text Syntax Information Item defined as follows:
If [parent member][member][text syntax] is not Null, then that is the value of textSyntax.
Otherwise, [type][text syntax] MUST NOT be Null, and that is the value of textSyntax.
The text value in initializationText MUST either match one of the entries in textSyntax[values], or
match one of the entries in textSyntax[patterns]. The initializationText value is determined to be a
match for a Value Syntax Information Item valueSyntax from textSyntax[values] with the following
process:
Let trimmedInput be a string defined as follows:
o If valueSyntax[trim whitespace] is true, trimmedInput is formed by removing any
whitespace from the start and end of initializationText
o Otherwise trimmedInput is initializationText
Let casedSyntaxValue and casedInput be two strings defined as follows
o If valueSyntax[is case sensitive] is true, casedSyntaxValue is valueSyntax[text], and
casedInput is trimmedInput
o Otherwise, caseSyntaxValue is formed by converting any letters in valueSyntax[text]
to their uppercase equivalents, and caseInput is formed by converting any letters in
trimmedInput to their uppercase equivalents
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initializationText matches valueSyntax if and only if casedSyntaxValue is equal to casedInput
The initializationText value is determined to be a match for a Pattern Syntax Information Item
patternSyntax from textSyntax[patterns] with the following process:
Let trimmedInput be a string defined as follows:
o If patternSyntax[trim whitespace] is true, trimmedInput is formed by removing any
whitespace from the start and end of initializationText
o Otherwise trimmedInput is initializationText
Let casedInput be a strings defined as follows
o If patternSyntax[is case sensitive] is true, casedInput is trimmedInput
o Otherwise, casedInput is formed by converting any letters in trimmedInput to their
uppercase equivalents
initializationText matches patternSyntax if and only if casedInput is a match for the regular
expression in patternSyntax[pattern]; Xaml Schema Infoset regular expressions use the
same formulation as those in XML Schema Definitions. See Appendix F of Part 2 of the XML
Schema specification [XML Schema Part 2].

4.2.2.6. Cannot Provide Initialization Text and Other Member Values
If the nodes [member nodes] contain an item whose [member] is the intrinsic x:InitializationText
(5.3.3), [member nodes] MUST NOT contain any other items other than the following two optional
items: an item whose [member] is the intrinsic x:Key Directive (5.3.5); an item whose [member] is
the intrinsic x:Uid Directive (5.3.6).
4.2.2.7. x:XData Only Valid in XData Members
If the nodes [type] is the intrinsic x:XData (5.2.23), [parent member][value type][is xdata] MUST be
True.
4.2.2.8. x:TypeExtension Must Have Valid Type
If the nodes [type] is the intrinsic x:TypeExtension (5.2.3), [member nodes] MUST contain exactly
one Member Node Information Item whose [member] is one of the following:
The intrinsic x:ConstructorArgs (5.3.2).
The intrinsic TypeExtension.Type (5.3.19).
The intrinsic TypeExtension.TypeName (5.3.20).
[member nodes] MUST NOT contain more than one of the above.
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4.2.2.9. x:StaticExtension Must Have Valid Member
If the nodes [type] is the intrinsic x:StaticExtension (5.2.2), then there MUST exist a Text Node
Information Item memberTextNode defined as follows:
If the nodes [member nodes] contains a single Member Node Information Item whose
[member] is the intrinsic x:ConstructorArgs (5.3.2), and this Member Node Information Item
contains a single Text Node Information Item, let memberTextNode be that Text Node
Information Item.
Otherwise, the nodes [member nodes] MUST include a Member Node Information Item
whose [member] is the intrinsic StaticExtension.Member (5.3.18) , and this Member Node
Information Item MUST contain a single Text Node Information Item; let memberTextNode
be that Text Node Information Item.
Let memberText be memberTextNode[text]. MemberText MUST be a DottedXamlName (6.5.1), and
the DottedXamlNames typename part MUST be a valid QName (as defined in section 4 of [XML
Namespaces]).
Let memberSchema be defined as follows:
If the typename part is a PrefixedName (as defined in section 4 of [XML Namespaces]) then
o This nodes [xml namespace mappings] MUST contain an XML Namespace Mapping
whose [prefix] matches the typenames Prefix (as defined in section 4 of [XML
Namespaces]); let nsUri be the [uri] of that XML Namespace Mapping.
o A schema MUST be available whose [target namespace] matches nsUri. Let
memberSchema be that schema.
Otherwise, [xml namespace mappings] MUST contain a mapping whose [prefix] is the empty
string, an a schema MUST be available whose [target namespace] matches the [namespace
name] of that mapping; let memberSchema be that schema.
memberSchema[types] MUST contain a XamlType Information Item whose [name] matches the
DottedXamlNames typename parts LocalName (as defined in section 4 of [XML Namespaces]) in
memberText. Call that XamlType Information Item memberType.
memberType[members] MUST contain a XamlMember Information Item whose [name] matches the
DottedXamlNames membername part in MemberText. Call that XamlMember Information Item
memberInfo.
isAssignableTo(memberInfo[value type], [parent member][member][value type]) MUST be True.
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4.2.2.10. Array Contents Must Be Of Correct Type
If an Object Node Information Items [type] is the intrinsic x:ArrayExtension (5.2.1), and if its
[member nodes] contains a member arrayItems whose [member] is the intrinsic
ArrayExtension.Items (5.3.16), and if its [member nodes] also contains a member arrayType whose
[member] is the intrinsic ArrayExtension.Type (5.3.17), then for each Object Node Information Item
item in arrayItems [values], isAssignableTo(item[type], arrayType) MUST be True.
4.2.2.11. Only Retrieved Objects May Use Assignable Types
If the nodes [type] is a member of one or more schemas [assignable types] and is not a member of
any schemas [types], the nodes [is retrieved] MUST be True.
4.2.3. Note (non-normative)
Since Xaml does not need to be represented as XML, it may seem odd to have an [xml namespace
mappings] property. The reason for this is to enable Xaml to use XML namespace prefixes as a
shorthand for referring to schemas.
4.3 Member Node Information Item
A Member Node Information Item represents one of a number of features. Properties, directives,
events, or initialization strings are all represented as Member Node Information Items.
Table 13: Member Node Information Item Properties
Name Type Purpose (non-normative)
[member] XamlMember Information Item Xaml Schema Infoset information item that
defines this member.
[parent object] Object Node Information Item The object on which this member has been
set.
[values] Ordered Collection of information
items; each item may be either an
Object Node Information Item, or a
Text Node Information Item
The value or values being set by this
member node.
[xml
namespace
mappings]
Set of XML Namespace Mappings The XML namespace mappings in effect at
this member.

4.3.1. Constraints
The Member Node Information Items in a well-formed Xaml Information Set MUST conform to the
rules defined in this section.
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4.3.1.1. Information Set Properties Must Be of Correct Type
Each property of a Member Node Information Item MUST have a value of the type specified for that
property in Table 13.
4.3.1.2. Multiple Values Only Allowed in List Content, Dictionary Content, or Constructor
Arguments
If [member] is not one of the x:Items (5.3.1), x:DirectiveChildren (5.3.12), or x:ConstructorArgs
(5.3.2) intrinsic items, then [values] MUST contain exactly one item. (Otherwise, it can contain 0 or
more such items.)
Note: all members may contain any number of objects of intrinsic type x:Code (5.2.22).
4.3.1.3. Intrinsic x:Items Member Only Allowed in List or Dictionary
If [member] is the intrinsic x:Items (5.3.1) member type, then either [parent object][type][is
dictionary] or [parent object][type][is list] MUST be True.
4.3.1.4. Dictionary Content Rules
If ([parent object][type][is dictionary] and [member] is the instrinsic x:Items (5.3.1)), the following
rules apply:
[values] MUST NOT contain any Text Node items.
Each Object Node Information Item dictItem in [values] MUST match at least one of the
following (and let the first of these rules that matches define keyMemberNode for that
dictItem):
o dictItem[member nodes] contains a Member Node Information Item that is the
x:Key directive (defined in 5.3.5).
o dictItem[member nodes] contains a Member Node Information Item whose
[member] is dictItem[type][dictionary key property].
For each Object Node Information Item dictItem in [values], the corresponding
keyMemberNode identified in the previous step MUST have a [values] that contains exactly
one item. That item, referred to here as keyValue, MUST be assignable to [parent
object][type][allowed key types], i.e., one of the following MUST be true:
o keyValue is a Text Node Information Item and [parent object][type][allowed key
types] contains either the x:String XamlType Information Item (5.2.6), or the
x:Object XamlType Information Item (5.2.5), or there is exactly one XamlMember
Information Item in [parent object][type][allowed key types] with a non-Null [text
syntax].
o keyValue is an Object Node Information Item, and [parent object][type][allowed key
types] contains a keyType for which isAssignableTo(keyValue[type], keyType) is True
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Each keyValue identified in the previous step MUST be unique within the scope of the
containing dictionary.
4.3.1.5. XML Data Rules
If [member][value type][is xdata] = True then
If [values] contains more than 0 items then:
o [values] MUST NOT contain more than one item.
o the one item in [values] MUST be a text node.
o The value of the text node MUST be well-formed XML, and any namespace prefixes
used within the XML MUST either be declared within the nested XML text, or be in
the [xml namespace mappings] of the containing Member Node Information Item.
4.3.1.6. x:Class Directive Rules
If [member] is the x:Class Directive (5.3.7), [parent object][parent member] MUST be Null (i.e., this
attribute may only be applied to the root node).
4.3.1.7. x:Subclass Directive Rules
If [member] is the x:Subclass Directive (5.3.8), [parent object][member nodes] MUST contain a
Member Node Information Item whose [member] is the x:Class Directive (5.3.7).
4.3.1.8. x:ClassModifier Directive Rules
If [member] is the x:ClassModifier Directive (5.3.9), [parent object][member nodes] MUST contain a
Member Node Information Item whose [member] is the x:Class Directive (5.3.7).
4.3.1.9. x:TypeArguments Directive Rules
If [member] is the x:TypeArguments Directive (5.3.11), [parent object][member nodes] MUST
contain a Member Node Information Item whose [member] is the x:Class Directive (5.3.7).
4.3.1.10. x:FieldModifier Directive Rules
If [member] is the x:FieldModifier Directive (5.3.10), the root nodes [member nodes] MUST contain
a Member Node Information Item whose [member] is the x:Class Directive (5.3.7).
4.3.2. Validity Constraints
A Member Node Information Item in a Xaml Information Set cannot be valid with respect to some
set of schemas unless it meets rules defined in this section.
4.3.2.1. Values Must Be of the Appropriate Type
For each item val in [values], one of the following MUST apply.
val is a Text Node Information Item and
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o Either [member] is x:Items (5.3.1) and [parent object][type][allowed types] contains
either the x:String (5.2.6), or the x:Object (5.2.5) XamlType Information Items
o or [member][value type] is either the x:String (5.2.6), or the x:Object (5.2.5)
XamlType Information Item
o or [member][text syntax] is not Null
o or [member][value type][text syntax] is not Null.
val is an Object Node Information Item and [member] is x:Items (5.3.1) and [member][value
type][allowed types] contains an allowedType for which isAssignableTo(val[type],
allowedType) is True.
val is an Object Node Information Item where val[type][types assignable to] contains the
intrinsic x:MarkupExtension (5.2.21), and [member] is x:Items (5.3.1) and [member][value
type][allowed types] contains an allowedType for which isAssignableTo(val[type][return
value type], allowedType) is True.
val is an Object Node Information Item and isAssignableTo(val[type], [member][value type])
is True.
val is an Object Node Information Item where val[type][types assignable to] contains the
intrinsic x:MarkupExtension (5.2.21), and isAssignableTo(val[type][return value type],
[member][value type]) is True.
4.3.2.2. If Member Non-Attached, Non-Directive, Element Type Must Have Member
If [member][is attachable] and [member][is directive] are both False, [parent
object][type][members] MUST contain [member].
4.3.2.3. Attached Member Target Type Must Match
If [member][is attachable] is True, and [parent object][type][members] does not contain [member],
isAssignableTo([parent object][type], [member][target type]) MUST be True.
4.3.2.4. Text Value of Non-Text Member Must Match Text Syntax
If [member][text syntax] is not Null, let textSyntax be [member][text syntax]; otherwise let
textSyntax be [member][value type][text syntax].
If [values] contains a single Text Node Information Item, and textSyntax is not Null, the [text] value
in the Text Node Information Item MUST either match one of the entries in textSyntax[values], or
match one of the entries in textSyntax[patterns]. The rules for determining a match are defined in
section 4.2.2.5 (Initialization Text Must Match Text Syntax).
4.3.2.5. Read-only Members
If [member][is read only] is True, [values] MUST contain just a single object node where [is
retrieved] is True.
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4.3.2.6. Names MUST Be Unique Within a Namespace Scope
Let nameMember of any Object Node Information Item be determined as follows:
If that Object Node Information Items [member nodes] contains an item whose [member]
is the intrinsic x:Name Directive (5.3.4), nameMember is that item.
If that Object Node Information Items [member nodes] contains an item whose [member]
is the Object Node Information Items [parent object][type][name property], nameMember
is that item.
If an Object Node Information Item has a nameMember, it is a named object, and its name is the
single value in nameMember[values]
If an Object Node Information Item is a named object, its name MUST be different from the name of
any other named object that shares the same namespace scope.
A Xaml processor MUST determine whether two Object Node Information Items share the same
namespace scope by walking up the tree by starting at [parent object] and then following [parent
object][parent member] until reaching either the root node, or an Object Node Information Item
whose [type][is name scope] is True. If this process ends at the same node for two different nodes,
those two nodes share a namespace scope.
4.3.2.7. x:Key Directive Rules
If [member] is the x:Key Directive (5.3.5), [parent object][parent member][parent object][type][is
dictionary] MUST be True.
4.3.2.8. x:FieldModifier Directive Rules
If [member] is the x:FieldModifier Directive (5.3.10), [parent object][member nodes] MUST contain
either a Member Node Information Item whose [member] is the x:Name Directive (5.3.4), or a
Member Node Information Item whose [member] is the same as this members [parent
object][type][name property].
4.3.2.9. Members of Type x:XamlType and Type Names Must Refer to Valid Type
If [member][value type] is the intrinsic x:XamlType (5.2.19), or if [member] is the intrinsic
TypeExtension.TypeName (5.3.20), or ([member] is the intrinsic x:ConstructorArgs (5.3.2) AND
[parent object][type] is the intrinsic x:TypeExtension (5.2.3)) then [values] MUST contain just a single
text node. Let typeText be that text nodes [text].
Let typeSchema be defined as follows:
If typeText is a PrefixedName (as defined in section 4 of [XML Namespaces]) then
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o This nodes [xml namespace mappings] MUST contain an XML Namespace Mapping
whose [prefix] matches the typeTexts Prefix (as defined in section 4 of [XML
Namespaces]); let nsUri be the [uri] of that XML Namespace Mapping.
o A schema whose [target namespace] matches nsUri MUST be available. Let
memberSchema be the schema.
Otherwise, [parent object][xml namespace mappings] MUST contain a mapping whose
[prefix] is the empty string, and a schema MUST be available whose [target namespace]
matches the [namespace name] of that mapping. let memberSchema be that schema.
memberSchema[types] MUST contain a XamlType Information Item whose [name] matches
typeTexts LocalName (as defined in section 4 of [XML Namespaces]) in MemberText. Let targetType
be that XamlType Information Item.
4.3.3. Notes (Non-Normative)
Validation rule 4.3.2.5 (Read-only Members) deals with the fact that this is meaningful:
<MyElement>
<MyElement.DictionaryMember>
<AnotherElement x:Key="myKey" />
</MyElement.DictionaryMember>
</MyElement>
As is this:
<MyElement>
<MyElement.DictionaryMember>
<DictionaryElement>
<AnotherElement x:Key="myKey" />
</DictionaryElement>
</MyElement.DictionaryMember>
</MyElement>
But this is not:
<MyElement>
<MyElement.DictionaryMember>
<DictionaryElement>
<AnotherElement x:Key="myKey" />
</DictionaryElement>
<AnotherElement x:Key="bar" />
</MyElement.DictionaryMember>
</MyElement>
In summary, either you can bring your own dictionary, or you can add items directly to the member
element as children to have them added to the dictionary, but you cant do both.
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4.4 Text Node Information Item
A Text Node Information Item represents a value in a member nodes [values] that contains text or
an XML literal.
Table 14: Text Node Information Item Properties
Name Type Purpose (non-normative)
[text] Text String The text value.
[parent member] Member Node Information
Item
The member of which this text is a value.

4.4.1. Constraints
The Text Node Information Items in a well-formed Xaml Information Set MUST conform to the rules
defined in this section.
4.4.1.1. Information Set Properties Must Be of Correct Type
Each property of a Text Node Information Item MUST have a value of the type specified for that
property in Table 14.
4.4.2. Notes (Non-Normative)
Whitespace is represented as a text node. There are special processing rules for handling
whitespace, because it is significant in some contexts, and ignorable in others. The Xaml information
set is the output of the process described in Section 6, Creating a Xaml Information Set from XML,
and all the rules for deciding whether to ignore white space are executed during that process.
Consequently, there is no need to represent whitespace differently in the Xaml infoset where
whitespace is preserved, it simply ends up inside text nodes.
XML literals (xData) are also represented as text nodes. It is possible to determine whether a
particular text node represents text or an XML literal by examining the text nodes [parent
member][member][value type][is xdata] member. Note that XML literals are not self-contained XML
documents: the literal can use the namespaces prefixes described in [parent member][xml
namespace mappings], and they also inherit xml:space and xml:lang attributes where present.
Note that the set of characters that may be used in [text] is not restricted to the subset defined for
the Char production defined in Section 2.2 of the XML specification ([XML]). However, the use of
characters outside the range acceptable in XML is discouraged.


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Section 5. Intrinsic Schema Information Items
This section defines an intrinsic set of schema information items that are implicitly available to all
Xaml Schema Information Sets and Xaml Information Sets.
5.1 Intrinsic Schema Information Items
The following Schema Information Items are available when processing any XML document as Xaml.
5.1.1. The x: Schema
The x: schema is so-called because its XML namespace is conventionally associated with the x:
prefix. It contains directives and types available across all Xaml vocabularies.
Table 15: Schema Information Item Property Values for x: Schema
Property Value
[target namespace] http://schemas.microsoft.com/winfx/2006/xaml
[types] The following XamlType Information Items: x:ArrayExtension (5.2.1),
x:StaticExtension (5.2.2), x:TypeExtension (5.2.3), x:NullExtension
(5.2.4), x:Object (5.2.5), x:String (5.2.6), x:Double (5.2.9), x:Boolean
(5.2.17), x:Array (5.2.18), x:XamlType (5.2.19), x:XamlEvent (5.2.20),
x:MarkupExtension (5.2.21), x:Code (5.2.22), and x:XData (5.2.23)
[directives] The following XamlMember Information Items: x:Items (5.3.1),
x:ConstructorArgs (5.3.2), x:InitializationText (5.3.3), x:Name
Directive (5.3.4), x:Key Directive (5.3.5), x:Uid Directive (5.3.6),
x:Class Directive (5.3.7), x:Subclass Directive (5.3.8), x:ClassModifier
Directive (5.3.9), x:FieldModifier Directive (5.3.10), and
x:TypeArguments Directive (5.3.11)
[compatible with schemas] Empty

5.1.2. The XML Namespace Schema
The XML Namespace Schema contains directives corresponding to the xml:lang, xml:space, and
xml:base attributes.
Table 16: Schema Information Item Property Values for x: Schema
Property Value
[target namespace] http://www.w3.org/XML/1998/namespace
[types] Empty
[directives] The following XamlMember Information Items: xml:lang Directive
(5.3.13), xml:space Directive (5.3.14), and xml:base Directive (5.3.15)
[compatible with schemas] Empty

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5.2 Intrinsic XamlType Information Items
The following sections define special types used for processing Xaml Instances.
Many of the XamlType Information Item properties are somewhat specialized the majority of
types use the same values for most of the properties. To make it easy to see the distinguishing
features of each type, only the properties that differ from the norm are listed. Table 17 shows the
values that properties have in the case where their type definition does not specify a value.
Table 17: Default XamlType Information Item Property Values
Property Value
[types assignable to] x:Object (5.2.5)
[is default constructible] True
[is nullable] True
[text syntax] Null
[content property] Null
[dictionary key property] Null
[name property] Null
[xml lang property] Null
[trim surrounding whitespace] False
[is whitespace significant
collection]
False
[is list] False
[is dictionary] False
[allowed types] Empty
[allowed key types] Empty
[is xdata] False
[is name scope] False
[constructors] Empty
[return value type] Null

5.2.1. x:ArrayExtension
This XamlType Information Item signifies that a list of items is to be treated as an array, where the
target programming system recognizes such a concept.
Table 18: XamlType Information Item Property Values for x:ArrayExtension
Property Value
[name] ArrayExtension
[members] ArrayExtension.Items (5.3.16);
ArrayExtension.Type (5.3.17)
[content property] ArrayExtension.Items (5.3.16)
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Note: the distinction between this and x:Array (5.2.18) is that x:ArrayExtension is concerned with
how to represent arrays in Xaml, whereas x:Array is the type of an array itself.
5.2.2. x:StaticExtension
This XamlType Information Item represents a markup extension type indicating that a static member
belonging to some particular type should be read.
Table 19: XamlType Information Item Property Values for x:StaticExtension
Property Value
[name] StaticExtension
[types assignable to] x:MarkupExtension (5.2.21); x:Object (5.2.5)
[members] StaticExtension.Member (5.3.18)
[constructors] Static Extension String Constructor (5.5.1)
[return value type] x:Object (5.2.5)

5.2.3. x:TypeExtension
This XamlType Information Item represents a markup extension type that evaluates to a x:XamlType
(5.2.19) object representing a particular type.
Table 20: XamlType Information Item Property Values for x:TypeExtension
Property Value
[name] TypeExtension
[types assignable to] x:MarkupExtension (5.2.21); x:Object (5.2.5)
[members] TypeExtension.Type (5.3.19);
TypeExtension.TypeName (5.3.20)
[constructors] Type Extension String Constructor (5.5.2)
[return value type] x:XamlType (5.2.19)

5.2.4. x:NullExtension
This XamlType Information Item represents a markup extension type that evaluates to a Null value.
Table 21: XamlType Information Item Property Values for x:NullExtension
Property Value
[name] NullExtension
[types assignable to] x:MarkupExtension (5.2.21); x:Object (5.2.5)
[members] Empty
[return value type] x:Object (5.2.5)

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5.2.5. x:Object
Xaml vocabularies that wish to be able to define members that can accept values of any type can
use x:Object as the [value type] of those members. Note that this specification does not assign any
intrinsic meaning to x:Object it only provides it as a common type for vocabularies that require this
idea. Since Xaml does not require vocabularies to support a root type or universal base class idea,
those that want this concept must opt in: a type will only be assignable to x:Object if the vocabulary
explicitly includes x:Object in that types [types assignable to].
Table 22: XamlType Information Item Property Values for x:Object
Property Value
[name] Object
[types assignable to] Empty
[is default constructible] False
[members] Empty

5.2.6. x:String
Type used to represent text strings.
Table 23: XamlType Information Item Property Values for x:String
Property Value
[name] String
[members] Empty

5.2.7. x:Char
Type used to represent a single text character.
Table 24: XamlType Information Item Property Values for x:Char
Property Value
[name] Char
[is nullable] False
[text syntax] x:Char Text Syntax (5.4.1)
[members] Empty

5.2.8. x:Single
Type representing a single-precision floating point numeric value. This type is not used within this
specification. It is provided because this type is widely used by providing this one definition, Xaml
vocabularies do not each need to define their own.
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Table 25: XamlType Information Item Property Values for x:Single
Property Value
[name] Single
[is nullable] False
[text syntax] x:Single Text Syntax (5.4.2)
[members] Empty

5.2.9. x:Double
Type representing a double-precision floating point numeric value. This type is not used within this
specification. It is provided because this type is widely used by providing this one definition, Xaml
vocabularies do not each need to define their own.
Table 26: XamlType Information Item Property Values for x:Double
Property Value
[name] Double
[is nullable] False
[text syntax] x:Double Text Syntax (5.4.3)
[members] Empty

5.2.10. x:Byte
Type representing an unsigned 8-bit byte. This type is not used within this specification. It is
provided because this type is widely used by providing this one definition, Xaml vocabularies do
not each need to define their own.
Table 27: XamlType Information Item Property Values for x:Byte
Property Value
[name] Byte
[is nullable] False
[text syntax] x:Byte Text Syntax (5.4.4)
[members] Empty

5.2.11. x:Int16
Type representing a signed 16-bit number. This type is not used within this specification. It is
provided because this type is widely used by providing this one definition, Xaml vocabularies do
not each need to define their own.
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Table 28: XamlType Information Item Property Values for x:Int16
Property Value
[name] Int16
[is nullable] False
[text syntax] x:Int16 Text Syntax (5.4.5)
[members] Empty

5.2.12. x:Int32
Type representing a signed 32-bit number. This type is not used within this specification. It is
provided because this type is widely used by providing this one definition, Xaml vocabularies do
not each need to define their own.
Table 29: XamlType Information Item Property Values for x:Int32
Property Value
[name] Int32
[is nullable] False
[text syntax] x:Int32 Text Syntax (5.4.6)
[members] Empty

5.2.13. x:Int64
Type representing a signed 64-bit number. This type is not used within this specification. It is
provided because this type is widely used by providing this one definition, Xaml vocabularies do
not each need to define their own.
Table 30: XamlType Information Item Property Values for x:Int64
Property Value
[name] Int64
[is nullable] False
[text syntax] x:Int64 Text Syntax (5.4.7)
[members] Empty

5.2.14. x:Decimal
Type representing a decimal number. This type is not used within this specification. It is provided
because this type is widely used by providing this one definition, Xaml vocabularies do not each
need to define their own.
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Table 31: XamlType Information Item Property Values for x:Decimal
Property Value
[name] Decimal
[is nullable] False
[text syntax] x:Decimal Text Syntax (5.4.8)
[members] Empty

5.2.15. x:Uri
Type representing a URI. This type is not used within this specification. It is provided because this
type is widely used by providing this one definition, Xaml vocabularies do not each need to define
their own.
Table 32: XamlType Information Item Property Values for x:Uri
Property Value
[name] Uri
[is nullable] False
[text syntax] x:Uri Text Syntax (5.4.9)
[members] Empty

5.2.16. x:Timespan
Type representing a time span. This type is not used within this specification. It is provided because
this type is widely used by providing this one definition, Xaml vocabularies do not each need to
define their own.
Table 33: XamlType Information Item Property Values for x:Timespan
Property Value
[name] Timespan
[is nullable] False
[text syntax] x:Timespan Text Syntax (5.4.10)
[members] Empty

5.2.17. x:Boolean
Type representing a Boolean value a value which may be either true or false.
Table 34: XamlType Information Item Property Values for x:Boolean
Property Value
[name] Boolean
[is nullable] False
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[text syntax] x:Boolean Text Syntax (5.4.11)
[members] Empty

5.2.18. x:Array
Type representing base class of arrays.
Table 35: XamlType Information Item Property Values for x:Array
Property Value
[name] Array
[is default constructible] False
[members] Empty
[is list] True
[allowed types] x:Object (5.2.5)

5.2.19. x:XamlType
Type for objects that represent types.
Table 36: XamlType Information Item Property Values for x:XamlType
Property Value
[name] XamlType
[is default constructible] False
[text syntax] x:XamlType Text Syntax (5.4.12)
[members] Empty
[return value type] Null

5.2.20. x:XamlEvent
Type for objects that represent event handlers.
Table 37: XamlType Information Item Property Values for x:XamlEvent
Property Value
[name] XamlEvent
[is default constructible] False
[text syntax] x:XamlEvent Text Syntax (5.4.14)
[members] Empty


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5.2.21. x:MarkupExtension
Well-known base type that indicates a type is a markup extension. Types indicate that they are
markup extensions by including this in their [types assignable to].
Table 38: XamlType Information Item Property Values for x:MarkupExtension
Property Value
[name] MarkupExtension
[is default constructible] False
[members] Empty

5.2.22. x:Code
Type of object nodes representing source code embedded in Xaml. (The meaning of this code is
determined by the Xaml processor. This specification simply defines the mechanism by which plain
text can be embedded in a Xaml Instance.)
Table 39: XamlType Information Item Property Values for x:Code
Property Value
[name] Code
[is default constructible] False
[is nullable] False
[members] Empty

5.2.23. x:XData
Type representing XML data islands.
Table 40: XamlType Information Item Property Values for x:XData
Property Value
[name] XData
[is default constructible] False
[members] Empty

5.3 Intrinsic XamlMember Information Items
This section defines the intrinsic members defined in the x: Schema and the XML Namespace
Schema.
Many of the XamlMember Information Item properties are somewhat specialized the majority of
members use the same values for some properties. To make it easy to see the distinguishing
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features of each member, only properties that differ from the norm are listed. Table 41 shows the
values that properties have in the case where their type definition does not specify a value.
Table 41: Default XamlMember Information Item Property Values
Property Value
[text syntax] Null
[is read only] False
[is static] False
[is attachable] False
[target type] Null
[allowed location] Any
[is event] False
[is directive] False
5.3.1. x:Items
Pseudo member used when an object node contains multiple values.
Table 42: XamlMember Information Item Property Values for x:Items
Property Value
[name] Items
[owner type] Null
[value type] x:Object (5.2.5)
[allowed location] None
[is directive] True
5.3.2. x:ConstructorArgs
Pseudo member used to represent the constructor argument list for a markup extension. The
markup extensions object nodes [member nodes] will contain a member for each named
parameter, and may also contain a member to represent the unnamed, ordered parameters. A
member node serving that purpose is identified by having its [member] refer to this
x:ConstructorArgs (5.3.2) intrinsic member.
Table 43: XamlMember Information Item Property Values for x:ConstructorArgs
Property Value
[name] ConstructorArgs
[owner type] Null
[value type] x:Object (5.2.5)
[allowed location] None
[is directive] True
5.3.3. x:InitializationText
Pseudo member used to hold the text string used when an object is initialized using text.
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Table 44: XamlMember Information Item Property Values for x:InitializationText
Property Value
[name] InitializationText
[owner type] Null
[value type] x:String (5.2.6)
[allowed location] None
[is directive] True
5.3.4. x:Name Directive
Directive used to set the name of an element. The meaning of a name is up to individual Xaml
processors to describe this specification simply provides a mechanism for associating a name with
an object node, and a mechanism by which a schema can indicate that a particular member is
equivalent to the x:Name directive.
Table 45: XamlMember Information Item Property Values for x:Name Directive
Property Value
[name] Name
[owner type] Null
[value type] x:String (5.2.6)
[is directive] True

5.3.5. x:Key Directive
Directive used to indicate the key of an object added to a dictionary.
Table 46: XamlMember Information Item Property Values for x:Key Directive
Property Value
[name] Key
[owner type] Null
[value type] x:Object (5.2.5)
[is directive] True
5.3.6. x:Uid Directive
Directive used to provide a unique identifier for localization purposes.
Table 47: XamlMember Information Item Property Values for x:Uid Directive
Property Value
[name] Uid
[owner type] Null
[value type] x:String (5.2.6)
[is directive] True
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5.3.7. x:Class Directive
Directive used to indicate the name of a class associated with a Xaml file. It is up to individual Xaml
processors to define the interpretation of this directive.
Table 48: XamlMember Information Item Property Values for x:Class Directive
Property Value
[name] Class
[owner type] Null
[value type] x:String (5.2.6)
[is directive] True
5.3.8. x:Subclass Directive
Directive used to indicate the name of a subclass associated with a Xaml file. It is up to individual
Xaml processors to define the interpretation of this directive.
Table 49: XamlMember Information Item Property Values for x:Subclass Directive
Property Value
[name] Subclass
[owner type] Null
[value type] x:String (5.2.6)
[is directive] True
5.3.9. x:ClassModifier Directive
Directive used to indicate the modifier of the class associated with a Xaml file. It is up to individual
Xaml processors to define the interpretation of this directive.
Table 50: XamlMember Information Item Property Values for x:ClassModifier Directive
Property Value
[name] ClassModifier
[owner type] Null
[value type] x:String (5.2.6)
[is directive] True
5.3.10. x:FieldModifier Directive
Directive used to indicate the modifier of the field associated with a named Xaml element. It is up to
individual Xaml processors to define the interpretation of this directive.
Table 51: XamlMember Information Item Property Values for x:FieldModifier Directive
Property Value
[name] FieldModifier
[owner type] Null
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[value type] x:String (5.2.6)
[is directive] True
5.3.11. x:TypeArguments Directive
Directive used to indicate the type arguments for the class associated with a Xaml file. It is up to
individual Xaml processors to define the interpretation of this directive.
Table 52: XamlMember Information Item Property Values for x:TypeArguments Directive
Property Value
[name] TypeArguments
[owner type] Null
[value type] x:String (5.2.6)
[is directive] True
5.3.12. x:DirectiveChildren
Pseudo member used to hold x:Code items.
Table 53: XamlMember Information Item Property Values for x:Items
Property Value
[name] DirectiveChildren
[owner type] Null
[value type] x:Code (5.2.22)
[allowed location] None
[is directive] True
5.3.13. xml:lang Directive
Directive used to represent the standard xml:lang attribute in a Xaml file.
Table 54: XamlMember Information Item Property Values for xml:lang Directive
Property Value
[name] TypeArguments
[owner type] Null
[value type] x:String (5.2.6)
[allowed location] AttributeOnly
[is directive] True
5.3.14. xml:space Directive
Directive used to represent the standard xml:space attribute in a Xaml file.
Table 55: XamlMember Information Item Property Values for xml:space Directive
Property Value
[name] space
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[owner type] Null
[value type] x:String (5.2.6)
[text syntax] xml:space Text Syntax (5.4.13)
[allowed location] AttributeOnly
[is directive] True
5.3.15. xml:base Directive
Directive used to represent the standard xml:base attribute in a Xaml file.
Table 56: XamlMember Information Item Property Values for xml:base Directive
Property Value
[name] base
[owner type] Null
[value type] x:String (5.2.6)
[allowed location] AttributeOnly
[is directive] True

5.3.16. ArrayExtension.Items
Content member for the x:ArrayExtension (5.2.1) type.
Table 57: XamlMember Information Item Property Values for ArrayExtension.Items
Property Value
[name] Items
[owner type] x:ArrayExtension (5.2.1)
[value type] x:Array (5.2.18)
[is read only] True
5.3.17. ArrayExtension.Type
Member of x:ArrayExtension (5.2.1) that indicates what type of elements the array contains.
Table 58: XamlMember Information Item Property Values for ArrayExtension.Type
Property Value
[name] Type
[owner type] x:ArrayExtension (5.2.1)
[value type] x:XamlType (5.2.19)
5.3.18. StaticExtension.Member
Identifies the static member whose value this extension returns.
Table 59: XamlMember Information Item Property Values for StaticExtension.Member
Property Value
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[name] Member
[owner type] x:StaticExtension (5.2.2)
[value type] x:String (5.2.6)
5.3.19. TypeExtension.Type
The XamlType this extension returns.
Table 60: XamlMember Information Item Property Values for TypeExtension.Type
Property Value
[name] Type
[owner type] x:TypeExtension (5.2.3)
[value type] x:XamlType (5.2.19)
5.3.20. TypeExtension.TypeName
The name of the XamlType this extension returns.
Table 61: XamlMember Information Item Property Values for TypeExtension.TypeName
Property Value
[name] TypeName
[owner type] x:TypeExtension (5.2.3)
[value type] x:String (5.2.6)
[text syntax] x:XamlType Text Syntax (5.4.12)

5.4 Intrinsic Text Syntax Information Items
This section defines the intrinsic Text Syntax Information Items.
This section uses a notational convention for representing the Value Syntax Information Items and
Pattern Syntax Information Items that make up a Text Syntax Information Item. They are listed as a
semicolon delimited sequence, or the word Empty to indicate that the relevant set contains no
items.
Each entry in the sequence for the [values] of a Text Syntax Information Item represents a Value
Syntax Information Item. The entry includes a string in double quotes representing the [text]
member of the Value Syntax Information Item. The string may optionally be followed by [is case
sensitive]=True, and/or [trim whitespace]=False. Where these values are not specified explicitly, [is
case sensitive] is False, and [trim whitespace] is True.
Each entry in the sequence for the [patterns] of a Text Syntax Information Item represents a Pattern
Syntax Information Item. The entry includes a string in double quotes representing the [pattern]
member of the Pattern Syntax Information Item. This string may optionall be followed by [is case
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sensitive]=False, and/or [trim whitespace]=False. Where these values are not specified explicitly, [is
case sensitive] is True, and [trim whitespace] is True.
5.4.1. x:Char Text Syntax
This text syntax defines the acceptable representations of values of type x:Char (5.2.7).
Table 62: Text Syntax Information Item Property Values for x:Char Text Syntax
Property Value
[values] Empty
[patterns] .

5.4.2. x:Single Text Syntax
This text syntax defines the acceptable representations of values of type x:Single (5.2.8).
Table 63: Text Syntax Information Item Property Values for x:Single Text Syntax
Property Value
[values] Infinity [is case sensitive]=True;
-Infinity [is case sensitive]=True;
NaN [is case sensitive]=True
[patterns] [+-]?(([\d,]+(\.\d*)?)|([\d,]*\.\d+))([eE][+-]?\d+)?
Informally, the [patterns] allows optional leading whitespace followed by an optional + or sign,
followed by a decimal number that takes one of two forms, optionally followed by an exponent. The
first acceptable form for the decimal number is a sequence of one or more decimal digits, optionally
followed by a decimal point which is followed by a sequence of zero or more decimal digits. (E.g. 1
or 1.01.) The second acceptable form for the decimal number is a sequence of zero or more
decimal digits, followed by a decimal point which is followed by a sequence of one or more decimal
digits. (E.g. .1 or 1.01.) The optional exponent must start with either e or E, it optionally
followed by a + or - sign, and then followed by a sequence of one or more decimal digits. Finally, the
number value may be followed by white space.

5.4.3. x:Double Text Syntax
This text syntax defines the acceptable representations of values of type x:Double (5.2.9).
Table 64: Text Syntax Information Item Property Values for x:Double Text Syntax
Property Value
[values] Infinity [is case sensitive]=True;
-Infinity [is case sensitive]=True;
NaN [is case sensitive]=True
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[patterns] [+-]?(([\d,]+(\.\d*)?)|([\d,]*\.\d+))([eE][+-]?\d+)?
Informally, the [patterns] allows optional leading whitespace followed by an optional + or sign,
followed by a decimal number that takes one of two forms, optionally followed by an exponent. The
first acceptable form for the decimal number is a sequence of one or more decimal digits, optionally
followed by a decimal point which is followed by a sequence of zero or more decimal digits. (E.g. 1
or 1.01.) The second acceptable form for the decimal number is a sequence of zero or more
decimal digits, followed by a decimal point which is followed by a sequence of one or more decimal
digits. (E.g. .1 or 1.01.) The optional exponent must start with either e or E, it optionally
followed by a + or - sign, and then followed by a sequence of one or more decimal digits. Finally, the
number value may be followed by white space.
5.4.4. x:Byte Text Syntax
This text syntax defines the acceptable representations of values of type x:Byte (5.2.10).
Table 65: Text Syntax Information Item Property Values for x:Byte Text Syntax
Property Value
[values] Empty
[patterns] \d+

5.4.5. x:Int16 Text Syntax
This text syntax defines the acceptable representations of values of type x:Int16 (5.2.11).
Table 66: Text Syntax Information Item Property Values for x:Int16 Text Syntax
Property Value
[values] Empty
[patterns] *+-]?\d+

5.4.6. x:Int32 Text Syntax
This text syntax defines the acceptable representations of values of type x:Int32 (5.2.12).
Table 67: Text Syntax Information Item Property Values for x:Int32 Text Syntax
Property Value
[values] Empty
[patterns] *+-]?\d+

5.4.7. x:Int64 Text Syntax
This text syntax defines the acceptable representations of values of type x:Int64 (5.2.13).
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Table 68: Text Syntax Information Item Property Values for x:Int64 Text Syntax
Property Value
[values] Empty
[patterns] *+-]?\d+

5.4.8. x:Decimal Text Syntax
This text syntax defines the acceptable representations of values of type x:Decimal (5.2.14).
Table 69: Text Syntax Information Item Property Values for x:Decimal Text Syntax
Property Value
[values] Empty
[patterns] *+-]?\d+

5.4.9. x:Uri Text Syntax
This text syntax defines the acceptable representations of values of type x:Uri (x:Uri).
Table 70: Text Syntax Information Item Property Values for x:Uri Text Syntax
Property Value
[values] Empty
[patterns] *

5.4.10. x:Timespan Text Syntax
This text syntax defines the acceptable representations of values of type x:Timespan (x:Timespan).
Table 71: Text Syntax Information Item Property Values for x:Timespan Text Syntax
Property Value
[values] Empty
[patterns] -?(\d*\.)?\d\d?:\d\d?:((\d\d?)|(\d?\d?\.\d*));
-?\d+

5.4.11. x:Boolean Text Syntax
This text syntax defines the acceptable representations of values of type x:Boolean (5.2.17).
Table 72: Text Syntax Information Item Property Values for x:Boolean Text Syntax
Property Value
[values] True; False
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[patterns] Empty
Informally, the [patterns] allows either the string true or false (with any mixture of upper or
lower case characters), optionally surrounded by whitespace.
5.4.12. x:XamlType Text Syntax
This text syntax defines the acceptable representations of values of type x:XamlType (5.2.19).
Table 73: Text Syntax Information Item Property Values for x:XamlType Text Syntax
Property Value
[values] Empty
[patterns] (*_\p{L}][\.-
_\p{L}\p{Nd}\p{Mc}]*:)?[_\p{Lu}\p{Ll}\p{Lo}\p{Lt}\p{Nl}\p{Lm}][_\p{Lu}\p{Ll}\p{
Lo}\p{Lt}\p{Nl}\p{Lm}\p{Nd}\p{Mn}\p,Mc-+* [trim whitespace]=False
Informally, the [patterns] allows an optional namespace prefix which, if present, must be followed
by a colon, followed by a XamlName.
5.4.13. xml:space Text Syntax
This text syntax describes the acceptable representations of values of the xml:space Directive
(5.3.14).
Table 74: Text Syntax Information Item Property Values for xml:space Text Syntax
Property Value
[values] default [is case sensitive]=True [trim whitespace]=False;
preserve [is case sensitive]=True [trim whitespace]=False
[patterns] Empty
5.4.14. x:XamlEvent Text Syntax
This text syntax describes the acceptable representations of event members.
Table 75: Text Syntax Information Item Property Values for x:XamlEvent Text Syntax
Property Value
[values] Empty
[patterns] *_\p{Lu}\p{Ll}\p{Lo}\p{Lt}\p{Nl}\p{Lm}][_\p{Lu}\p{Ll}\p{Lo}\p{Lt}\p{Nl}\p{Lm}\p
{Nd}\p{Mn}\p,Mc-+* [trim whitespace]=False
Informally, the [patterns] allows any XamlName.
5.5 Intrinsic Constructor Information Items
This section defines the Constructor Information Item used by the XamlType Information Items
defined in section 5.2, Intrinsic XamlType Information Items.
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5.5.1. Static Extension String Constructor
This is the only Constructor Information Item for the x:StaticExtension type (5.2.2). It takes a single
parameter, a string, which is logically equivalent to the StaticExtension.Member (5.3.18) member.
Table 76: Constructor Information Item Property Values for Static Extension String Constructor
Property Value
[arguments] [ x:String (5.2.6) ]

5.5.2. Type Extension String Constructor
This is the only Constructor Information Item for the x:TypeExtension type (5.2.3). It takes a single
parameter, a string, which is logically equivalent to the TypeExtension.TypeName (5.3.20) member.
Table 77: Constructor Information Item Property Values for x:TypeExtension
Property Value
[arguments] [ x:String (5.2.6) ]








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Section 6. Creating a Xaml Information Set from XML
An XML document is a Xaml Document if a well-formed Xaml Information Set can be created from
the XML documents XML Infoset. The conversion process is performed with reference to a set of
schemas that includes those defined in Section 5, Intrinsic Schema Information Items. Additional
vocabulary-specific schemas may (and usually will) also be used as part of the conversion process.
In order to construct a Xaml Information set from an XML document, that documents XML Infoset is
processed with the rules defined in section 6.6. If the rules in section 6.6 are successfully executed
without error, the resulting Xaml Information Set must conform to the constraints in Section 4 in
order for the XML document to be said to be a Xaml Document.
6.1 Unavailability of Xaml Schemas
XML documents may contain features for which schema information items are not available. This
makes it impossible to determine that the document is valid. Implementations MAY choose to
process documents despite the absence of schemas, producing a well-formed but potentially invalid
Xaml Information Set.
Implementations that choose to handle Xaml in the absence of schema MUST generate placeholder
Xaml Schema Information Set items to stand in for the missing schema. For example, a Member
Node Information Item has a [member] property that refers to a XamlMember Information Item.
Without this, there would be no way to know the members name. Section 6.6 includes rules for
generating suitable information items.
6.2 Processing Errors
Not all XML documents can be successfully converted to a Xaml Information Set. However, it may be
useful for Xaml processors to continue processing in the face of an error. This specification does not
define what Xaml processors should do in the face of an error Xaml processors MAY terminate
processing in the face of an error or they MAY attempt to continue processing.
Where the rules in this section identify an error, they incorporate a description. For example, a
particular scenario might be described as an Unknown namespace error. The error text is
informative, and Xaml processors are not required to do anything with that text.
6.3 Markup Compatibility
XML documents containing Xaml may use the Markup Compatibility and Extensibility conventions
defined in Part 5 of ECMA-376 [MarkupCompat]. Implementations that convert XML into a Xaml
Information Set can process documents in two modes with respect to markup compatibility: raw,
and preprocessed. Xaml processors that support XML MUST support at least one of these modes.
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6.3.1. Raw Mode
In raw mode, elements and attributes in the XML document from the markup compatibility
namespace are processed in exactly the same way as any other elements and attributes, forming
object, member, and text nodes as normal.
Raw mode is suitable for applications that need to preserve as much of the original documents
structure as possible. A Xaml editor might use this mode.
6.3.2. Preprocessed Mode
In preprocessed mode, the input XML infoset is transformed by processing the content according to
the rules defined in the ECMA Markup Compatibility Specification [MarkupCompat] content is
ignored or substituted where appropriate. The markup compatibility elements and attributes are
then removed. The resulting XML infoset becomes the input to the conversion process described in
this section.
6.3.3. Subsumption Behavior
Section 10.2 of the Markup Compatibility specification requires markup consumers to declare which
subsumption behavior is used when processing an element from an older namespace that carries a
prefixed attribute from a newer, subsuming namespace. In a Xaml Document, if the attribute name
contains a . then the expanded name refers to the new namespace, if not, it refers to no
namespace.
6.4 XML Information Set References
The XML processing rules take an XML Information Set [XML Infoset] as input. To indicate that a
particular item is an XML Information Set information item, it is referred to as XML:type, where type
is one of the XML Information Set information item types:
Table 78: XML Information Set Reference Names
Name in This Specification Full Name in XML Information Set
XML:document Document Information Item
XML:element Element Information Item
XML:attribute Attribute Information Item
XML:namespace Namespace Information Item
XML:character Character Information Item

6.5 Definitions
The following definitions are used in the conversion process.
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6.5.1. DottedXamlName
A DottedXamlName is a string that conforms to the following grammar (using the syntax defined in
RFC4234 [ABNF]):
DottedXamlName = XamlName "." XamlName
The XamlName production was defined in section 2.2.
The first XamlName in a DottedXamlName is referred to as the typename. The second XamlName is
referred to as the membername.
6.5.2. Collapsible Whitespace Characters
The characters subject to whitespace collapsing are the following three Unicode code points:
Table 79: Collapsible Whitespace Characters
Unicode Code Point Character
0020 Space
000A LineFeed
0009 Tab
Note that it is intentional that this is not a complete list of all whitespace Unicode code points. There
are other Unicode codepoints that represent forms of whitespace, but those do not get collapsed.
6.5.3. Linefeed Collapsing Characters
The Unicode code points and surrogates in Table 80 and Table 81 are identified as Linefeed
Collapsing characters, and are subject to special rules for whitespace collapsing:
Table 80: Linefeed Collapsing Code Points
Code Point Range (Inclusive) Characters
1100 11FF Hangul
2E80 2FD5 CJK and KangXi Radicals
2FF0 2FFB Ideographic Description
3040 309F Hiragana
30A0 30FF Katakana
3100 312F Bopomofo
3130 318F Hangul Compatibility Jamo
3190 319F Kanbun
31F0 31FF Katakana Phonetic Extensions
3400 4DFF CJK Unified Ideographs Extension A
4E00 9FFF CJK Unified Ideographs
A000 A4CF Yi
AC00 D7A3 Hangul Syllables
F900 FAFF CJK Compatibility
FF00 FFEF Halfwidth and Fullwidth Forms
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Table 81: Linefeed Collapsing Surrogates
Surrogate Range (Inclusive) Characters
20000 2A6D6 CJK Unified Ext. B
2F800 2FA1D CJK Compatibility Supplement
The special rules for these characters are defined later in this specification.
6.5.4. Authoritative Schema
For an XML:element e, if a Xaml Schema is available whose [target namespace] matches
e[namespace name], that schema is the authoritative schema.
For an XML:attribute attr, the authoritative schema is determined as follows:
If attr[namespace name] has a value, one of the following two rules applies:
if a schema is available whose [target namespace] matches the attributes namespace, that
schema is the authoritative schema.
if no schema is available whose [target namespace] matches the attributes namespace, this
is an Unknown namespace error.
If attr[namespace name] does not have a value, one of the following rules applies:
if the attr[local name] matches the XamlName production, the authoritative schema is the
authoritative schema of the element to which the attribute has been applied.
if the attr[local name] matches the DottedXamlName production:
o if a schema is available whose [target namespace] matches the default namespace
in scope, that is the authoritative schema.
o If no schema is available whose [target namespace] matches the default namespace
in scope, this is an Unknown namespace error.
Otherwise, there is no authoritative schema.
The rules in 6.6 use the syntax schema(node) where node is either an XML:element or an
XML:attribute. This is shorthand meaning the authoritative schema for either an element or an
attribute node.
6.6 Document Processing Rules
This section defines rules for processing an XML Infoset to generate a Xaml Information Set. Each
rule takes inputs that determine the context in which the rule is executed. Each rule has a single
output. Most rules return a Xaml Information Set item, except for a few utility rules used to avoid
duplication of logic. (E.g., some rules return a Xaml Schema Information Set item.)
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Many of the rules involve several steps. These rules define variables to hold the intermediate
results. For clarity, rule inputs and variables are shown with distinctive formatting, as shown in Table
82.
Example Meaning
myInput
An input to a rule
myVariable
A variable whose value is the intermediate result of a step of a rule
Table 82: Rule input and variable formatting
Rules often define some steps in terms of other rules. The following formatting convention is used
to denote an invocation of a rule:
Let resultVar = Invoke Member Node Creation from Content
(containingMember ::= contentMember,
memberType ::= memberType,
childNodes ::= npChildren,
preserveXmlSpace ::= space)
This signifies that a rule variable called resultVar should be given the value returned by invoking
the rule named Member Node Creation from Content, passing various rule variables in as the
inputs to the rule.
Processing MUST begin by passing the XML:document information item of the information set of the
XML document to be processed as the xmlDocument input to the XML:document Processing rule
defined in 6.6.1.
6.6.1. XML:document Processing
This rule has the following input:
Name Type Purpose (non-normative)
xmlDocument
XML:document The XML document to be processed.
The output of this rule is a Xaml Information Set Document Information Item.
If xmlDocument[children] contains a document type definition (DTD), it is a Xaml documents must
not contain DTDs error.
If the document contains entity references other than lt, gt, amp, apos, or quot, it is a Xaml
documents must not contain entity references other than lt, gt, amp, apos, or quot error. This rule
also implies that xmlDocument[notations] and xmlDocument[unparsed entities] must be empty.
A Xaml Document processor MUST support the following encodings in Xaml Documents: UTF-8 and
UTF-16. (These encodings are defined in section 3.9 of The Unicode Standard [Unicode], in
definitions D92 and D91 respectively.)
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Let xamlRoot = Invoke Object Node Creation from an XML:element
(xmlObjectElement ::= xmlDocument[document element],
parentPreservesXmlSpace ::= False)
Comments and processing instructions in xmlDocument[children] MUST be ignored.
Let result be a Document Information Item initialized as follows:
result[document object] = xamlRoot
This rule MUST return result.
6.6.2. Object Node Creation from an XML:element
This rule has the following input:
Name Type Purpose (non-normative)
xmlObjectElement
XML:element An XML element representing an
object.
parentPreservesXmlSpace
Boolean Indicates whether
xml:space="preserve" is in effect
for this nodes parent.
The output of this rule is a Xaml Information Set Object Node Information Item.
Let objectType be a XamlType Information Item determined as follows:
If schema(xmlObjectElement)[types] contains a type t where t[name] matches
xmlObjectElement[local name], let objectType be that t.
Otherwise, if schema(xmlObjectElement)[types] contains a type t where t[name] matches
the concatenation of xmlObjectElement*local name+ and Extension and t[types assignable
to] contains the x:MarkupExtension type (5.2.21), let objectType be that t.
Otherwise, it is an unknown element type error.
Let preserveChildXmlSpace be a Boolean value determined as follows:
If xmlObjectElement[attributes] contains an XML:attribute corresponding to the standard
xml:space attribute, let preserveChildXmlSpace be True if the attributes *normalized
value+ is preserve, and let it be False otherwise.
Otherwise, let preserveChildXmlSpace be parentPreservesXmlSpace.
Let childXmlNodes be xmlObjectElement[children]
If objectType is either of the intrinsic types x:Code (5.2.22) or x:XData (5.2.23), then:
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Let literalResult be an Object Node Information Item initialized as follows:
literalResult[type] = objectType
literalResult[member nodes] is set to a single text node, whose value is a string
representation of xmlObjectElement[children]
literalResult[parent member] is not determined by the rules in this section it is set
by the rule from which this rule was invoked, or in the case of the root element, it is
Null.
literalResult[is retrieved] is False
literalResult[xml namespace mappings] is generated as follows:
Invoke Xml Namespace Mapping Conversion
(xmlNamespaces ::= xmlObjectElement[in-scope namespaces])
The output of this rule is literalResult.
Otherwise, proceed with the remaining steps in this rule.
The nodes in childXmlNodes are processed in phases to produce a sequence of information items.
The following list shows a summary of the phases, which are described in detail below.
1. Conversion: childXmlNodes is converted into a sequence of items, where each item is
either an object node, a member node, or a text node.
2. Whitespace removal: text nodes between member nodes, or before the first member node,
or after the last member node, are stripped out.
3. Content wrapping: text or object nodes are wrapped in implicit member nodes; the
sequence now contains only member nodes.
Conversion
Conversion builds an intermediate result, convertedChildNodes, which is an ordered sequence
that may contain Object Node Information Items, Member Node Information Items, or Text Node
Information Items. It is generated by applying the first of the following steps that matches to each
xmlChild in childXmlNodes in document order.
If xmlChild is an XML:element:
o If xmlChild[local name] is a XamlName:
Let convertedObject = Invoke Object Node Creation from an XML:element
(xmlObjectElement ::= xmlChild,
parentPreservesXmlSpace ::= preserveChildXmlSpace)
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then append convertedObject to convertedChildNodes.
o Otherwise, if xmlChild[local name] is a DottedXamlName:
Let convertedMember = Invoke Member Node Creation from an XML:element
(xmlObjectElement ::= xmlChild)
then append convertedMember to convertedChildNodes.
o Otherwise, it is an Invalid element name syntax error.
If xmlChild is an XML:character:
o If convertedChildNodes ends in a Text Node Information Item, append the
Unicode character identified by xmlChild[character code] to that nodes [text].
o Otherwise, append to convertedChildNodes a new Text Node Information Item
with a [text] value containing the Unicode character identified by
xmlChild[character code]. (The [parent member] will be set later.)
An XML node of any other type is ignored, and will not cause an item to be added to
convertedChildNodes.
If convertedChildNodes contains any Object Node Information Item with a [type] of the intrinsic
x:Code (5.2.22), remove these from convertedChildNodes. If convertedChildNodes contains an
Member Node Information Items whose [values] contain any Object Node Information Items with a
[type] of the intrinsic x:Code (5.2.22), remove these from that [values].
Let codeItems be the Object Node Information Items removed by the steps in the previous
paragraph. If codeItems is not empty, add a new Member Node Information Item called
directiveChildren initialized as follows:
directiveChildren[member] is the intrinsic x:DirectiveChildren (5.3.12) XamlMember
Information Item
directiveChildren[values] contains the Object Node Information Items in codeItems, with
the [parent member] of each item set to directiveChildren
directiveChildren[parent object] is set later on in this section.
directiveChildren[xml namespace mappings] is generated as follows:
Invoke Xml Namespace Mapping Conversion
(xmlNamespaces ::= xmlObjectElement[in-scope namespaces])

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Whitespace Removal
Whitespace removal takes convertedChildNodes and strips out whitespace between member
nodes to form a new intermediate result, strippedChildNodes. For the purposes of this section,
whitespace characters are those listed in section 6.5.2, Collapsible Whitespace Characters.
Removal proceeds as follows:
For each node convertedChild in convertedChildNodes:
If convertedChild is a Text Node Information Item, and if its [text] contains only
whitespace, then ignore the node if any of the following is true:
o convertedChild is the first item in convertedChildNodes, and is followed
immediately by a member node.
o convertedChild immediately follows a member node and is followed immediately
by a member node.
o convertedChild immediately follows a member node and is the last item in
convertedChildNodes, and either strippedChildNodes already contains one or
more text nodes, or convertedChildNodes contains a member node whose
[member] is objectType[content property].
Otherwise, append convertedChild to strippedChildNodes.
Content Wrapping
Content wrapping proceeds as follows. Define contentMember and contentMemberType with the
first of the following to match:
If objectType[content property] is not Null, let contentMember be objectType[content
property], and let contentMemberType be contentMember[value type].
Otherwise, let contentMember be the intrinsic x:Items (5.3.1), and let contentMemberType
be objectType.
Let attributeMembers be the set of Member Node Information Items generated by applying the
following invocation for each xmlAttribute in xmlObjectElement[attributes]:
Invoke Member Node Creation from an XML:attribute
(xmlAttribute ::= xmlAttribute,
objectType ::= objectType,
namespacesInScope ::= xmlObjectElement[in-scope namespaces])
Let members be a set of Member Node Information Items. If all of the following are True:
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strippedChildNodes contains exactly one Text Node Information Item and
strippedChildNodes either contains no other items, or contains only a Member Node
Information Items whose [member] is the intrinsic x:DirectiveChildren (5.3.12).
attributeMembers is either empty, or contains only Member Node Information Items
whose [member] is either the x:Key Directive (5.3.5) or the x:Uid Directive (5.3.6).
either contentMember[text syntax] is not Null or objectType[text syntax] is not Null.
then let members contain just a single Member Node Information Item initTextMember initialized
as follows:
initTextMember[member] is the intrinsic x:InitializationText (5.3.3) member
initTextMember[parent object] is set later in this rule
initTextMember[values] contains the single text node in strippedChildNodes
Otherwise, let members be the union of the following three sets:
attributeMembers.
The set of Member Node Information Items generated by applying the following invocation
for each consecutive sequence npChildren of non-member-node items in
strippedChildNodes:
Invoke Member Node Creation from Content
(containingMember ::= contentMember,
memberType ::= contentMemberType,
childNodes ::= npChildren,
preserveXmlSpace ::= preserveChildXmlSpace)
The set of items in strippedChildNodes that are Member Node Information Items.
Let result be an Object Node Information Item initialized as follows:
result[type] = objectType
result[member nodes] is set to members, with [parent object] of each Member Node
Information Item set to result
result[parent member] is not determined by the rules in this section it is set by the rule
from which this rule was invoked, or in the case of the root element, it is Null.
result[is retrieved] is False
result[xml namespace mappings] is generated as follows:
Invoke Xml Namespace Mapping Conversion
(xmlNamespaces ::= xmlObjectElement[in-scope namespaces])
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This rule MUST return result.
6.6.2.1. Notes (non-normative)
The content wrapping process can end up producing more than one content member. For example,
consider the following XML:
<MyObject>
Some content
<MyObject.Prop>BarValue</MyObject.Prop>
More content
</MyObject>
If <MyObject> represents an object node, its [member nodes] will contain two content nodes, one
representing each piece of text. The well-formedness rules in Section 4 require that Xaml processors
identify this as an error a Xaml Information Set is not well formed if an object node contains two
member nodes with the same XamlMember Information Item. (See 4.2.1.3.) However, for some
applications (e.g. Xaml editors) it may be useful to carry on document processing even when a
document is known not to be valid. The example XML shown above is conceptually equivalent to
this:
<MyObject>
<MyObject.Content>
Some content
</MyObject.Content>
<MyObject.Prop>BarValue</MyObject.Prop>
<MyObject.Content>
More content
</MyObject.Content>
</MyObject >
Where Content is MyObjects content member. This makes it more obvious why this is not
considered well-formed Xaml. The error is the same in both cases the same member appearing
twice in one element. The only difference in the first example is that the content member has not
been spelled out as a member element.
6.6.3. Member Node Creation from an XML:attribute
This rule has the following inputs:
Name Type Purpose (non-normative)
xmlAttribute
XML:attribute An XML attribute present on an element
representing an object.
objectType
XamlType Information
Item
The type of object that the attributes
containing element represents.
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namespacesInScope
Set of
XML:namespaces
Namespaces in scope for the element
that contains this attribute
The output of this rule is a Xaml Information Set Member Node Information Item.
Let member be a XamlMember Information Item determined by the following:
If xmlAttribute[local name] is a XamlName
o If schema(xmlAttribute)[types] contains objectType
schema(xmlAttribute)[compatible with schemas] contains a schema whose [types]
contains objectType or a schema is available whose [types] contains objectType
and whose [compatible with schemas] contains schema(xmlAttribute)
Define memberInfo as follows:
Let memberInfo = Invoke Member Lookup
(definingType ::= objectType,
memberName ::= xmlAttribute[local name])
If memberInfo is not Null, let member be memberInfo
o If the previous step does not determine a value for member, if there exists a
XamlMember Information Item in schema(xmlAttribute)[directives] for which the
[name] property matches xmlAttribute[local name], let member be that
XamlMember Information Item.
o If neither of the previous steps determines a value for member, it is an unknown
member error.
If xmlAttribute[local name] is a DottedXamlName
o Let typeName be the DottedXamlNames typename.
o Let memberName be the DottedXamlNames membername.
o Let definingType be a XamlType Information Item determined as follows
If schema(xmlAttribute)[types] contains objectType and
objectType[types assignable to] contains a XamlType Information Item
where [name] matches typeName, let definingType be objectType.
Otherwise, if schema(xmlAttribute)[types] contains a XamlType
Information Item xt where xt[name] matches typeName, let definingType
be xt.
Otherwise, it is an unknown type error.
o Define memberInfo as follows:
Let memberInfo = Invoke Member Lookup
(definingType ::= definingType,
memberName ::= memberName)
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o If memberInfo is not Null, let member be memberInfo.
o Otherwise it is an unknown member error.
Otherwise, it is an invalid attribute syntax error.
If member[allowed location] is None, it is an unknown member error.
Let attributeText be the string xmlAttribute[normalized value].
The member will contain a single value, attributeValue, which is calculated as follows:
Let attributeValue = Invoke Value Creation from Attribute Text
(valueText ::= attributeText,
attributeMemberType ::= member[value type],
namespacesInScope ::= namespacesInScope)
If attributeValue is an Object Node Information Item, its [parent member] is set to result. If
attributeValue is a Text Node Information Item, its [parent member] is set to result.
Let result be a Member Node Information Item initialized as follows:
result[member] = member
result[parent object] is not set by this rule it is set by the invoker of this rule
result[values] = a collection containing a single item, attributeValue
This rule MUST return result.
6.6.3.1. Notes (non-normative)
The rules in this section consider attributes that match the XamlName production, and that are not
qualified with a namespace prefix to be equivalent to attributes explicitly placed in the same
namespace as their containing element. For example, this
<q:MyObject Prop="42" />
Is equivalent to this:
<q:MyObject q:Prop="42" />
In particular, note that this means an unqualified attribute is not necessarily considered to be in the
default namespace. That will only be the case if the element happens to be in the default
namespace in scope. So if d: is a prefix for the namespace that is also the default namespace in
scope, the following are all equivalent:
<AnotherObject AnotherProp="99" />
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<d:AnotherObject AnotherProp="99" />
<AnotherObject d:AnotherProp="99" />
<d:AnotherObject d:AnotherProp="99" />
Attributes representing attached properties are handled differently. If they are not qualified with a
namespace prefix, they are considered to be equivalent to attributes explicitly placed in the default
namespace.
6.6.4. Value Creation from Attribute Text
This rule has the following inputs:
Name Type Purpose (non-normative)
valueText
Text String The text value to represent as a value. (Either an
attribute value, or a string nested inside a markup
extension attribute value.)
attributeMemberType
XamlType
Information Item
Type of value this text represents
namespacesInScope
Set of
XML:namespaces
The set of namespaces in scope on the element in
which this text value appears.
The output of this rule will either be an Object Node Information Item or a Text Node Information
Item.
Let result be defined as follows:
If valueText begins with , and does not begin with ,-, the value is an Object Node
Information Item determined as follows:
Let result = Invoke Object Node Creation from a Markup Extension in an Attribute
(attributeText ::= valueText,
namespacesInScope ::= namespacesInScope)

Otherwise, let unescapedValue be a Text String defined as follows:
o if valueText begins with ,-, unescapedValue is valueText with the leading ,-
removed.
o Otherwise, unescapedValue is valueText.
Let result be a new Text Node Information Item whose [text] is unescapedValue and
whose [parent member] is set by the invoker of this rule.
This rule MUST return result.
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6.6.5. Member Node Creation from an XML:element
This rule has the following inputs:
Name Type Purpose (non-normative)
xmlMemberElement
XML:element An XML element representing a member.
containingType
XamlType
Information Item
The type of the object node to which this
member will belong.
parentPreservesXmlSpace
Boolean Indicates whether xml:space="preserve" is in
effect for this nodes parent.
The output of this rule is a member node. This does not set the [parent object] property the
invoker of this rule must provide the value for that property.
If xmlMemberElement[attributes] is not empty, it may only contain a single attribute, whose [local
name] MUST be Uid, and whose *namespace name+ MUST be the [target namespace] of the x:
Schema (http://schemas.microsoft.com/winfx/2006/xaml). If xmlMemberElement[attributes]
contains anything other than this, it is a member elements cannot contain attributes error. Xaml
processors MAY choose to continue processing by ignoring any attributes. (Note that in the case
where the x:Uid (5.3.6) attribute is present, it is ignored no Xaml Information Set elements are
created to represent the attribute. The only difference between this and any other attribute is that
the x:Uids presence is not deemed to be an error.)
This rule is only invoked when xmlMemberElement[local name] is a DottedXamlName. Let
elementTypeName and elementMemberName be the typename and membername respectively of this
DottedXamlName.
Let ownerType be a XamlType Information Item determined as follows:
If schema(xmlMemberElement)[types] contains a type t where t[name] matches
elementTypeName, then:
o If containingType[types assignable to] contains t, let ownerType be
containingType.
o Otherwise, let ownerType be t.
Otherwise, it is an unknown element type error.
Let resolvedMember be a XamlMember Information Item determined as follows:
Define memberInfo as follows:
Let memberInfo = Invoke Member Lookup
(definingType ::= ownerType,
memberName ::= elementMemberName)
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If memberInfo is not Null, let resolvedMember be memberInfo.
Otherwise, it is a member not found error.
If memberInfo [allowed location] is not Any, it is a member not found error.
Let convertedChildNodes be an ordered sequence that may contain Object Node Information
Items or Text Node Information Items. (Note: the following part is similar to the conversion process
in the Object Node Creation from an XML:element rule. The difference is that here, member
elements are not permitted as children, since these elements are already inside a member element.)
It is generated by applying the first of the following steps that matches to each xmlChild in
childXmlNodes in document order.
If xmlChild is an XML:element:
o If xmlChild[local name] is a XamlName:
Let convertedObject = Invoke Object Node Creation from an XML:element
(xmlObjectElement ::= xmlChild,
parentPreservesXmlSpace ::= parentPreservesXmlSpace)
then append convertedObject to convertedChildNodes.
o Otherwise, if xmlChild[local name] is a DottedXamlName, it is a Member elements
may not be nested directly inside of another member element error.
o Otherwise, it is an Invalid element name syntax error.
If xmlChild is an XML:character:
o If convertedChildNodes ends in a Text Node Information Item, append the
Unicode character identified by xmlChild[character code] to that nodes [text].
o Otherwise, append to convertedChildNodes a new Text Node Information Item
with a [text] value containing the Unicode character identified by
xmlChild[character code]. (The [parent member] will be set later.)
An XML node of any other type is ignored, and will not cause an item to be added to
convertedChildNodes.

Let result = Invoke Member Node Creation from Content
(containingMember ::= resolvedMember,
memberType ::= resolvedMember[value type],
childNodes ::= convertedChildNodes,
preserveXmlSpace ::= parentPreservesXmlSpace)

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This rule MUST return result.
6.6.6. Member Node Creation from Content
This rule has the following inputs:
Name Type Purpose (non-normative)
containingMember
XamlMember Information Item The kind of member to create
memberType
XamlType Information Item The type of the member. (This is not always
the same as containingMember[value
type]. If this rule is invoked for the implicit
content of a list-like object node,
containingMember will be the intrinsic
x:Items (5.3.1) member, while memberType
will be the containing objects type.)
childNodes
Ordered Collection of items,
where each item is either an
Object Node Information Item
or a Text Node Information
Item
The text and object nodes to be processed
and wrapped
preserveXmlSpace
Boolean

Indicates whether XML space preservation
is on for the elements to be processed.
namespacesInScope
Set of XML:namespaces Namespaces in scope for the element that
contains this content.
The output of this rule is a Member Node Information Item.
For the purposes of this section, whitespace characters are those listed in section 6.5.2,
Collapsible Whitespace Characters. If preserveXmlSpace is False, apply the following steps:
For each Text Node Information Item in childNodes, any linefeed character (LF Unicode
Code Point 000A) both preceded and followed by characters in the ranges defined in section
6.5.3, Linefeed Collapsing Characters is removed.
For each Text Node Information Item in childNodes, replace any sequence of whitespace
characters with a single space.
If childNodes contains at least one Text Node Information Item, trim any leading
whitespace from the first Text Node Information Item; if this leaves the nodes [text] empty,
remove the node from childNodes.
If childNodes contains at least one Text Node Information Item, trim any trailing
whitespace from the last text node; if this leaves the nodes [text] empty, remove the node
from childNodes.
For each object node obn in childNodes, if obn[type][trim surrounding whitespace] is True
apply the following rules:
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o If childNodes contains a text node as the item before obn, trim any trailing
whitespace from that text node; if this leaves the text node empty, remove it from
childNodes.
o If childNodes contains a text node as the item after obn, trim any leading
whitespace from that text node; if this leaves the text node empty, remove it from
childNodes.
If memberType[is whitespace significant collection] is False, then for each text node tn in
childNodes, trim leading and trailing whitespace; if this leaves the text node empty, remove it from
childNodes.
Let outputValues be an ordered collection of information items, where items are either Object
Node Information Items, or Text Node Information Items, determined as follows:
If either memberType[is list] or memberType[is dictionary] are True, and childNodes does not
contain a single Object Node Information Item obj where [type][types assignable to]
contains memberType then
let retrievedContentMember be a new Member Node Information Item where
retrievedContentMember[member] is the intrinsic x:Items (5.3.1) XamlMember
Information Item
retrievedContentMember[values] is childNodes
retrievedContentMember[parent object] the retrievedMemberValue defined next
let retrievedValue be a new Object Node Information Item where
retrievedValue[type] is memberType
retrievedValue[member nodes] contains just retrievedContentMember
retrievedValue[parent member] is set below
retrievedValue[is retrieved] is True
retrievedValue[xml namespace mappings] is is generated as follows:
Invoke Xml Namespace Mapping Conversion
(xmlNamespaces ::= namespacesInScope)

and let outputValues contain just retrievedValue.
Otherwise let outputValues be childNodes.
Let result be a new Member Node Information Item prop, initialized as follows:
result [member] is containingMember
result [parent object] is supplied by the invoker of this rule
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result [values] outputValues, where for each text node tn in values set tn[parent member]
to prop; for each object node on in value set on[parent member] to prop
This rule MUST return result.
6.6.7. Object Node Creation from a Markup Extension in an Attribute
This rule has the following inputs:
Name Type Purpose (non-normative)
attributeText
Text String The text value of the attribute to be handled
as a markup extension.
containingElementSchema
Schema Information
Item
The schema of the element that contains this
attribute
namespacesInScope
Set of
XML:namespaces
Namespaces in scope for the element that
contains this attribute
The output of this rule is an object node.
Handling of Markup Extension attribute values is performed in two steps. First, the value MUST be
parsed. Then the resulting parse tree MUST be converted into Xaml Information Set nodes.
6.6.7.1. Markup Extension Parsing
The attributeText input MUST match the MarkupExtension production in the following grammar
(using the syntax defined in RFC4234 [ABNF]):
MarkupExtension = "{" TYPENAME 0*1Arguments "}"
Arguments = (NamedArgs / (PositionalArgs 0*1("," NamedArgs))
NamedArgs = NamedArg *("," NamedArg)
NamedArg = MEMBERNAME "=" STRING
PositionalArgs = NamedArg / (STRING 0*1( "," PositionArgs))

TYPENAME, MEMBERNAME and STRING above are special they are not defined in the grammar
because they are terminals as far as this ABNF grammar is concerned. This is because Markup
Extensions have slightly unusual tokenization rules. With normal ABNF, the input to the grammar is
a sequence of characters. But with Markup Extensions, a more complex tokenization process is
performed, which presents attributeText as a sequence consisting of the tokens shown in Table
83.
Table 83: Markup Extension tokens
Token Name Description
"{" Opening brace
"}" Closing brace
"=" Equals sign
"," Comma
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TYPENAME String representing the name of a type. Follows a "{" token, space
delimited.
MEMBERNAME String representing the name of a type. Precedes an "=" token. Delimited
by any of "{" "}" "," or "=" tokens.
STRING String representing the value of a member. Delimited by any of {},=
tokens.

The tokenizer treats as whitespace the characters identified in section 6.5.2, Collapsible
Whitespace Characters (i.e. the Unicode code points 0009, 000A, and 0020).
The tokenizer consumes characters in attributeText and generates tokens as follows:
The tokenizer starts by consuming the initial "{" (Unicode code point 007B) and generating a "{"
token.
The tokenizer consumes any whitespace characters that immediately follow the "{" character, and
does not produce a token to represent these whitespace characters.
Next, the tokenizer generates a TYPENAME token to represent the sequence of non-whitespace
characters that immediately follows the "{" character. The tokenizer consumes all the characters up
to, but not including the first character that is either whitespace or a "}" (Unicode code point 007D)
character, and those consumed characters are the TYPENAMEs value.
Next, the tokenizer consumes all characters up to but not including the first non-whitespace
character, does not produce a token to represent these whitespace characters.
The tokenizer proceeds by executing the following rules until all the characters in attributeText
have been consumed:
If the next character is a "}" (Unicode code point 007D) consume the character and generate a "}"
token.
If the next character is an "=" (Unicode code point 003D) consume the character and generate an
"=" token.
If the next character is a "," (Unicode code point 002C) consume the character and generate a ","
token.
If the next character is not one of ,-=,then it is the start of either a MEMBERNAME or a STRING, To
determine which kind of token to produce, the tokenizer MUST first read a text value (see below),
and then examine (but not consume) the character immediately following this text value. If the
character is =, the token is a MEMBERNAME. Otherwise it is a STRING. If the token is a
MEMBERNAME, any leading and trailing whitespace is removed from the text value.
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The text value of either a MEMBERNAME or STRING is read as follows. Leading whitespace
characters are consumed without being represented in the generated token. If the first non-
whitespace character is a quote (either Unicode code point 0022, Quotation Mark, or 0027,
Apostrophe), the tokenizer proceeds as follows:
The first quote is consumed and is not represented in the tokens value.
The text value becomes the characters up to but not including the next matching quote (i.e.
a character of the same code point as the opening quote) that is not preceded by a \
character. All these characters and also the closing quote are consumed. Any \ characters
in the resulting text value are removed.
Whitespace characters following the closing quote are consumed, and are not represented
in the token.
But if the first non-whitespace character of the text value is not a quote, then instead, the text value
is formed as follows. Initialize the running brace total to 0, then repeat the following rules until they
determine that the process is complete:
If the next character is a "\" (Unicode code point 005C), consume that "\" without adding it
to the text value, then consume the following character and append that to the value.
If the next character is a "{" add one to the running brace total, and consume the character,
appending it to the value.
If the next character is a "}", then the behaviour depends on the running brace total:
o If the running brace total is zero, do not consume the "}", do not append any more
to the text value; the text value reading process is now complete.
o If the running brace total is non-zero, consume the "}", append it to the value,
subtract one from the running brace total, and continue the text value reading
process.
If the next character is a "," or and "=", do not consume that character; the text reading
process is now complete.
Otherwise, consume the character and append it to the value.
The resulting sequence of characters then has leading and trailing whitespace characters removed.
The result is the value text.
6.6.7.2. Converting Parsed MarkupExtension to Xaml Information Set Nodes
The parsing procedure described in the previous will result in a parse tree with a MarkupExtension
production at its root. This is converted into Xaml Information Set nodes as follows.
Let extensionType be a XamlType Information Item determined as follows:
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Let typeName be the text value of the TYPENAME production of the root MarkupExtension
production.
If typeName is not a QName (as defined in section 4 of [XML Namespaces]), it is a bad type
extension name error.
Let extensionSchema be a Schema Information Item:
o If typeName is an UnprefixedName (as defined in section 4 of [XML Namespaces]),
let extensionSchema be containingElementSchema.
o If typeName is a PrefixedName (as defined in section 4 of [XML Namespaces]);
perform the following steps:
Let typeNamespaceUri be the [uri] of the XML Namespace Mapping in
namespacesInScope whose [prefix] matches the typeNames Prefix (as
defined in section 4 of [XML Namespaces]); if no such XML Namespace
Mapping exists, it is a unrecognized namespace prefix error.
Let extensionSchema be the schema whose [target namespace] matches
typeNamespaceUri. If no such schema is available, this is an Unknown
namespace error.
Let typeLocalName be the typeNames LocalPart (as defined in section 4 of [XML
Namespaces]).
Let extensionType be the XamlType Information Item in extensionSchema[types] whose
[name] matches the concatenation of typeLocalName and the string Extension; if no such
XamlType Information Item exists or if extensionType[types assignable to] does not include
the intrinsic x:MarkupExtension (5.2.21), let extensionType be the XamlType Information
Item in extensionSchema[types] whose [name] matches typeLocalName; if
extensionType[types assignable to] does not include the intrinsic x:MarkupExtension
(5.2.21), or if no such XamlType Information Item exists it is a unknown markup extension
error.
Let namedArgs be the set of NamedArg productions in the parse tree.
Let namedMembers be a set of Member Node Information Items generated as follows. For each
namedArg in namedArgs perform the following steps:
Let memberName be the MEMBERNAME production in namedArg
If memberName is not a QName (as defined in section 4 of [XML Namespaces]), it is a bad
member name error; if it is a QName, let memberLocalName be the LocalPart of the QName
Let memberSchema be defined as follows:
o If memberName is a UnprefixedName (as defined in section 4 of [XML Namespaces]),
let memberSchema be extensionSchema.
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o Otherwise, memberName is a PrefixedName (as defined in section 4 of [XML
Namespaces]); perform the following steps:
let memberNamespaceUri be the [uri] of the XML Namespace Mapping in
namespacesInScope whose [prefix] matches the memberNames Prefix (as
defined in section 4 of [XML Namespaces]) if no such XML Namespace
Mapping exists, it is a unrecognized namespace prefix error.
Let memberSchema be the schema whose [target namespace] matches
memberNamespaceUri. If no such schema is available, this is an Unknown
namespace error.
Let member be the Member Node Information Item this named argument represents,
determined as follows:
o If memberLocalName is a XamlName:
If memberSchema[types] does not contain extensionType, then it is a
markup extension named members MUST either be in the same schema as
the extension, or be attached members error.
Define memberInfo as follows:
Let memberInfo = Invoke Member Lookup
(definingType ::= extensionType,
memberName ::= memberLocalName)
If memberInfo is not Null, let member be memberInfo.
Otherwise, it is an unknown member error.
o Otherwise, If memberLocalName is a DottedXamlName:
Let typeName be the DottedXamlNames typename.
Let memberName be the DottedXamlNames membername.
Let definingType be a XamlType Information Item determined as follows
If memberSchema[types] contains a XamlType Information Item
where [name] matches typeName, let definingType be that type.
Otherwise, it is an unknown type error.
Define memberInfo as follows:
Let memberInfo = Invoke Member Lookup
(definingType ::= definingType,
memberName ::= memberName)
If memberInfo is not Null, let member be memberInfo
Otherwise it is an unknown member error.
Let memberValueText be the STRING production in namedArg.
Define memberValue as follows:
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Let memberValue = Invoke Value Creation from Attribute Text
(valueText ::= memberValueText,
attributeMemberType ::= member[value type],
namespacesInScope ::= namespacesInScope)

Defined namedMember node as a new Member Node Information Item initialized as follows:
namedMember[member]is member
namedMember[values] contains just memberValue
namedMember[parent object] is set later in this rule
Add resulting node to namedMembers.
Let positionalArgs be the set of STRING productions that are descendants of the PositionalArgs
production in the Arguments production in MarkupExtension production, ordered by increasing
depth in the parse tree.
Let positionalArgValues be an ordered sequence of Object Node Information Items and Text
Node Information Items generated as follows. Let constructorInfo be the Constructor Information
Item for the type whose [arguments] contains as many items as there are in positionalArgs. For
each positionalArg in positionalArgs perform the following steps:
Let argumentType be the Nth item in constructorInfo[arguments] where N is the
characterised thus: the current positionalArg is the Nth item in positionalArgs.
Calculate argValue, the value of the argument, thus:
Let argValue = Invoke Value Creation from Attribute Text
(valueText ::= argValueText,
attributeMemberType ::= argumentType,
namespacesInScope ::= namespacesInScope)
Append argValue to positionalArgValues.
If positionalArgValues is non-empty, let positionalArgsMember be a new member node where:
positionalArgsMember[member] is the intrinsic x:ConstructorArgs (5.3.2)
positionalArgsMember[values] is positionalArgValues, where each Object Node
Information Item has its [parent member] set to positionalArgsMember and each
Text Node Information Item has its [parent member] set to
positionalArgsMember
positionalArgsMember[parent object] is set below.
Otherwise, positionalArgValues is empty, in which case let positionalArgsMember be Null.
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Let allArgs be a set of Member Node Information Items that contains all the items in
namedMembers, and, if positionalArgsMember is non-Null it also contains positionalArgsMember.
Let result be a new Object node:
result[type] is extensionType
result[member nodes] is allArgs, where the [parent object] property of each item is set to
result
result[parent member] is
result[is retrieved] is False
result[xml namespace mappings] is namespacesInScope
This rule MUST return result.
6.6.8. Member Lookup
This rule has the following inputs:
Name Type Purpose (non-normative)
definingType
XamlType
Information Item
The type on which to look up the member.
memberName
Text String The name of the member to find
The rules output is a XamlMember Information Item.
If definingType[members] contains a member prop where prop[name] matches memberName, this
rule MUST return prop. Otherwise, this rule MUST return Null.
6.6.9. Xml Namespace Mapping Conversion
This rule has the following inputs:
Name Type Purpose (non-normative)
xmlNamespaces
Set of
XML:namespace
A set of XML namespace mappings from an
XML Infoset
The rules output is a set of XML Namespace Mappings, generated as follows:
For each XML:namespace xmlNsMapping in xmlNamespaces create an XML Namespace Mapping,
setting [uri] to xmlNsMapping[namespace name] and [prefix] to xmlNsMapping[prefix]. This rule
MUST return all of the XML Namespace Mappings thus generated.



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Appendix A: References

RFC 2119
Key words for use in RFCs to Indicate Requirement Levels, ed. S. Bradner. March 1997.
http://www.ietf.org/rfc/rfc2119.txt
XML
Extensible Markup Language (XML) 1.0 (Fourth Edition), W3C, eds. Tim Bray, Jean Paoli, C.M.
Sperberg-McQueen, Eve Maler, Franois Yergeau. 29 September 2006.
http://www.w3.org/TR/REC-xml
XML Infoset
XML Information Set (Second Edition), W3C, eds. John Cowan, Richard Tobin. 4 February 2004.
http://www.w3.org/TR/xml-infoset/
XML Namespaces
Namespaces in XML 1.0 (Second Edition), W3C, eds. Tim Bray, Dave Hollander, Andrew Layman,
Richard Tobin. 16 August 2006.
http://www.w3.org/TR/REC-xml-names/
XML Schema Part 2
XML Schema Part 2: Datatypes Second Edition, W3C, eds Paul V. Biron, Kaiser Permanente,
Ashok Malhotra. 28 August 2004.
http://www.w3.org/TR/xmlschema-2/
The Unicode Standard
The Unicode Consortium. The Unicode Standard, Version 5.0.0, defined by: The Unicode
Standard, Version 5.0, (Boston, MA, Addison-Wedley, 2007. ISBN 0-321-48091-0).
http://www.unicode.org/versions/Unicode5.0.0/
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URI
RFC 3986: Uniform Resource Identifier (URI): Generic Syntax, T. Berners-Lee, R. Fielding, and L.
Masinter, eds. IETF (Internet Engineering Task Force), January 2005.
http://www.ietf.org/rfc/rfc3986.txt
ABNF
RFC 4234: Augmented BNF for Syntax Specifications: ABNF, M D. Crocker, Ed. and P. Overell,
IETF (Internet Engineering Task Force), October 2005.
http://www.ietf.org/rfc/rfc4234.txt
Markup Compatibility and Extensibility
Part 5: Markup Compatibility and Extensibility (ECMA-376), ECMA, December 2006.
http://www.ecma-international.org/publications/standards/Ecma-376.htm




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Appendix B: Microsoft .NET Framework Behavior
The information in this specification is applicable to the following versions of the Microsoft product:
.NET Framework 3.0
.NET Framework 3.5
Exceptions, if any, are noted below. Unless otherwise specified, any statement of optional behavior
in this specification prescribed using the terms SHOULD or SHOULD NOT implies .NET Framework
behavior in accordance with the SHOULD or SHOULD NOT prescription. Unless otherwise specified,
the term MAY implies that .Net Framework does not follow the prescription.