This document is no longer maintained. See XML processing and DOM Document Type Definitions specification.
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© ‐ Wakaba.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License,
Version 1.2
or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front‐Cover Texts, and no Back‐Cover
Texts. A copy of the license is
available at <http://www.gnu.org/copyleft/fdl.html>
.
This section describes the status of this document at the time of its publication. Other documents might supersede this document.
This document is a working draft, produced as part of the
Whatpm
subproject of the
manakai
project. It might be updated, replaced, or obsoleted by
other documents at any time. It is inappropriate to
cite this document as other than work in progress
.
The scope of this specification is explicitly limited to the Whatpm implementation. It is not the purpose of this specification to define a general guideline to parse or to check XML documents. This specification does not try to define a new version of XML at all.
This version of the specification supports the fourth edition of XML 1.0 and the second edition of XML 1.1. The fifth edition of XML 1.0 might be supported in a later version. XML namespaces specifications is expected to be supported in a later version of this specification.
Comments on this document are welcome and may be sent to the author.
Translations of thie document might be available. The English version of the document is the only normative version.
This section is non‐normative.
This specification defines how the parsing and the conformance checking of XML documents should be implemented in the Whatpm XML parser and conformance checker.
It is not the purpose of this specification to define, e.g., how to parse XML documents in general; its scope is explicitly limited to the Whatpm implementation.
Much of invalid (well-formed or not) XML document parsing and XML document / XML DOM conformance is left undefined so that this document provides a guideline for conformance checkers.
The key words MUST
,
MUST NOT
,
SHOULD
,
SHOULD NOT
, and
MAY
in this
document are to be interpreted as described in
RFC
2119
[KEYWORDS].
All examples and notes in this specification are non‐normative, as are all sections explicitly marked non‐normative. Everything else in this specification is normative.
Algorithm is normative but non-normative. In addition, the order in which errors are raised is undefined.
This document sometimes cites parts of XML 1.0 specification by hyperlinks. When the document being processed is an XML 1.1 document, however, corresponding parts of the XML 1.1 specification should be consulted instead.
Conceptually, validation of an XML document is split into two stages for the purpose of this specification: the XML document parsing stage and the DOM XML conformance checking stage.
The input to the XML document parsing stage is a byte sequence representing the parsed XML document (and any additional metadata), and the output are a DOM tree representing the XML document and zero or more errors. The processor that implements this stage is called parser. Requirements for a parser are defined in the section of Parsing an XML Document.
The input to the DOM XML conformance chcking stage is a DOM tree, and the output are zero or more errors. The processor that implements this stage is called conformance checker. Requirements for a conformance checker are defined in the section of Checking an XML DOM Tree.
An error is ...
If a Document
node has no
xml-well-formedness-error, entity-error, and unknown-error,
then it is well-formed. If a well-formed Document
node has no xml-validity-error, it is valid.
A well‐formed Document
can be safely serialized
into a well‐formed XML document. A valid Document
can be easily serialized into a valid XML document.
To be a conforming validating XML processor, ...
Errors are classified into these error categories:
entity-error
@@
This algorithm does not support
DOM tree with one or more EntityReference
nodes. It is expected that any entity references are expanded
at the parse time and any unexpandable entity references
make parse time errors raised so that never result in
DOM tree with EntityReference
nodes.
round-trip-error
round-trip-warning
A round-trip-warning
will be raised when a construct, which might not be restored to the same
construct when it is serialized and then re-parsed by a conforming
processor, is encountered.
For a Comment
node a
round-trip-warning
will
be raised, since XML processors are not required to
report texts of comments for applications.
unknown-error
?xml-misc-error
xml-misc-fatal-error
xml-misc-recommendation
An
xml-misc-recommendation
will be raised if a SHOULD‐level requirement
in XML specification is not met.
xml-validity-error
xml-well-formedness-error
If an xml-well-formedness-error
is raised,
it would not be possible to generate an XML serialization that
would match to the appropriate production rule and that would not
violate to any well‐formedness constraint in XML
specification [XML10,
XML11].
misc-info
A misc-info
is raised when some status information
on parsing or checking process that are considered useful for debugging
and so on is available. It by no means implies the non-conformance of
the document.
@@ TODO: #dt-atuseroption at user option (MAY or MUST), #dt-compat for compatibility, #dt-interop for interoperability
TODO: XML 1.1, XML Namespace 1.0/1.1, xml:base, xml:id
TODO: XML "error"/"fatal error" is not always non-conforming (only when MUST or SHOULD).
When a byte stream that represents an XML document is given to a parser, it MUST create a DOM tree according to relevant specifications [XML10, XML11, XMLNAMES10, XMLNAMES11, DOM3CORE, WEBDOMCORE, DOMDTDEF, MANAKAIDOMEXT].
The parser MAY continue the parsing of the document even after a fatal error (as defined by the relavant specifications) is encountered. How the parsing ought to be continued is not defined by this specification.
A future version of this specification might define the entire parser in terms of input stream preprocessor, tokenizer, and tree constructor.
In addition, the following requirements are applied to the parser:
xml-misc-error
.
Document
node
for the document entity or an Entity
node for a general
entity) to true
.
@@ flag must be checked later
UTF-16
but
the input byte stream for the entity does not begin with the
BOM, then the parser
MUST raise an
xml-misc-error
.
xml-misc-recommendation
.
amp
, lt
, gt
,
apos
, or quot
, then the parser
MUST raise
xml-misc-recommendation
(s).
entities
attribute of the DocumentType
node MUST contain a NamedNodeMap
object
whose first five items are as follows:
Entity
node whose nodeName
attribute
is amp
. It contains a Text
node whose
data
attribute is set to &
.
Entity
node whose nodeName
attribute
is lt
. It contains a Text
node whose
data
attribute is set to <
.
Entity
node whose nodeName
attribute
is gt
. It contains a Text
node whose
data
attribute is set to >
.
Entity
node whose nodeName
attribute
is quot
. It contains a Text
node whose
data
attribute is set to "
.
Entity
node whose nodeName
attribute
is apos
. It contains a Text
node whose
data
attribute is set to '
.
EntityValue
part of the general entity declaration contains a bare U+003C
LESS-THAN SIGN
(<
) character, then the parser
MUST raise an
xml-misc-warning
.
Name
is equal to the Name
of the element type
declaration, then the parser MUST raise an
xml-validity-error
.
Name
is equal to the Name
of the attribute
definition list declaration, then the parser MUST
raise an
xml-misc-warning
.
Name
is equal to the Name
of the attribute
definition (whether or not in the same attribute definition list
declaration), then the parser MUST raise an
xml-misc-warning
.
If the entity declaration declares a general entity, the following is applied:
Name
is lt
or amp
If the entity declaration does not declare an internal entity,
or if the replacement text of the entity is not the escaped form of
<
(if lt
) or &
(if
amp
), then the parser MUST raise an
xml-misc-error
.
In other word, the character in the EntityValue
has to be double-escaped.
Name
is gt
, quot
, or
apos
If the entity declaration does not declare an internal entity,
or if the replacement text of the entity is not equal to or not the
escaped form of >
(if gt
), "
(if
quot
), or '
(if apos
), then the
parser MUST raise an
xml-misc-error
.
In other word, the character in the EntityValue
has to be single- or double-escaped.
If the entity declaration has to be ignored since there has already
been declared an entity with the same Name
as the declaration,
then the parser MUST raise a
misc-info
and abort these steps.
Five predefined entities, i.e. amp
, lt
,
gt
, quot
, and apos
, are always
declared implicitly and therefore any declaration for such an entity
always raises an
misc-info
.
If the entity declaration declares a parameter entity and the
Name
of the entity begins with the string xml
(in any combination of upper- and lowercase letters), then the parser
MUST raise an
xml-misc-warning
.
If the entity declaration contains the EntityValue
,
then for each occurence of any references to unparsed entities in the
EntityValue
, the parser MUST raise an
xml-misc-error
.
If the entity declaration declares a general entity, then an
Entity
node MUST be created and
appended to the NamedNodeMap
object in the
entities
attribute of the DocumentType
node.
Read the external entity
If the replacement text of the entity is read, then parse the
replacement text as if it were referenced from the content of an
element (with no namespace bindings). If no @@ parse error
is raised by the parsing process, then the nodes generated by the
parsing MUST be appended to the Entity
node. The parse error MUST NOT be propagated to
the entire parsing process. Other kinds of errors
MUST be propagated. The first parse error
MUST abort the internal parsing process.
@@ better wording
@@ prop
Then, the Entity
node and its descendant
MUST be marked as read-only.
Name
is equal to the Name
of the notation
declaration, then the parser MUST raise an
xml-validity-error
.
Name
of the tag is not declared by a processed
element type declaration as EMPTY
content, then the parser
MUST raise an
xml-misc-recommendation
.
Name
of the tag is declared by a processed element
type declaration as EMPTY
content, then the parser
MUST raise an
xml-misc-recommendation
.
The parser MUST set the normalized value of
the attribute to the value
attribute of the Attr
node created for the attribute.
That is, any entity reference has to be expanded. Unexpanded entity references in attribute values are discarded.
xml:space
attribute
xml:space
attribute to the value
attribute
of the Attr
node created for the attribute even if the
normalized value is different from default
or
preserve
.
Process as follows:
standalone
pseudo-attribute set to
yes
xml-well-formedness-error
.
xml-validity-error
.
In any of two cases above, process as follows:
IGNORE
d section.
standalone
pseudo-attribute of the
XML declaration (if any) is set to yes
.
entity-error
.
allDeclarationsProcessed
@@ ref
attribute of the Document
node MUST be
set to false
.
Process as follows:
Name
of the entity reference is either
amp
, lt
, gt
, quot
,
or apos
, then abort these steps.
standalone
pseudo-attribute set to
yes
xml-well-formedness-error
.
xml-validity-error
.
In any of two cases above, process as follows:
entity-error
.
@@ entity declared WFC?
Comment
node MUST be created
and inserted appropriately.
The parser MUST try to read any entity referenced by general or parameter entity references and the external subset entity, if any in the document type definition.
Well-formedness constraints. When the parser
detects a voilation to one of certain well-formedness constraints, it
MUST raise an xml-well-formedness-error
.
The list of such well-formed constraints is as follows:
Validity constraints. When the parser detects a
violation to one of certain validity contraints, it MUST raise an xml-validity-error
. The
list of such validity constraints is as follows:
Other creteria. If the parser detects a violation
to one of certain additional constraints, it MUST raise an xml-misc-recommendation
.
The list of such constraints is as follows:
For interoperability, if a parameter-entity reference appears in achoice
,seq
, orMixed
construct, its replacement text SHOULD contain at least one non-blank character, and neither the first nor last non-blank character of the replacement text SHOULD be a connector (|
or,
).
External parsed entities SHOULD each begin with a text declaration.
The parser MUST act as if it is a validating XML processor for the purpose of informing of white space characters appearing in element content (See Section 2.10 of the XML specification).
In other word, the isElementContentWhitespace
attribute
of Text
nodes has to be set appropriately. Note that the
value of the attribute will be set to false
for any
Text
node in the content of an element whose declaration
is not processed.
The parser MUST raise at least one xml-well-formedness-error
if the entity
it parses does not match to the appropriate production rule in the XML
specification. As an exception to this requirement, it MAY choose not to raise such an error if the error
will be raised by the conformance checker when the conformance checker
checks
the Document
object produced by the parser.
The following algorithms and definitions are applied to XML documents; especially, they are not applied to HTML documents.
The XML version of a node is
the XML version of the document to which the node belongs.
For a Documemt
node, the XML version
of the document is the value of the xmlVersion
attribute of the node. For a DocumentType
node whose
ownerDocument
attribute is set to null
,
the XML version of the document is 1.0
.
For any other node, the XML version of the document
is that of the Document
node contained in the
ownerDocument
attribute of the node.
To to validate an XML string (s), the following algorithm MUST be used:
Char10
,
then raise an
xml-well-formedness-error
.CompatChar10
,
then raise an
xml-misc-warning
.ControlChar10
,
then raise an
xml-misc-warning
.U+000D
CARRIAGE RETURN
character, then
raise a
round-trip-error
.
@@ We should not raise duplicate errors for U+000D
in attribute values. In addition, we should support a mode where
U+000D will be serialized as
(so that no round-trip-error
will be raised).To
validate a
Name
(s), the following
algorithm MUST be used:
xml-well-formedness-error
.
Abort these steps.NameStartChar10
, then raise
an
xml-well-formedness-error
.NameChar10
, then raise an
xml-well-formedness-error
.xml
(in any
case combination), then raise an
xml-misc-warning
.
@@ except for attribute names xml:lang
,
xml:space
.To
validate
an NCName
(s), the
following algorithm MUST be used:
To validate a public identifier (pid), the following algorithm MUST be used:
null
, abort these steps.PubidChar
, then
raise an
xml-well-formedness-error
.U+0009
CHARACTER TABULATION
,
U+000A
CARRIAGE RETURN
,
and U+000D
LINE FEED
characters, if the first character of pid is
U+0020
SPACE
character,
if the last character of pid is U+0020
SPACE
character, or if there is a
U+0020
SPACE
character
immediately followed by another U+0020
SPACE
character in pid, then it is a
round-trip-error
.
Is this really a roundtripness problem? XML spec
does only define the way to match public identifiers in fact, no
canonical form.To validate a system identifier (sid), the following algorithm MUST be used:
null
, abort these steps.U+0022
QUOTATION MARK
("
) and
U+0027
APOSTROPHE
('
) characters, raise an
xml-well-formedness-error
.U+0023
NUMBER SIGN
(#
)
character, then raise an
xml-misc-error
.Node
The algorithm to check a node (n) is defined as following:
Attr
nodelocalName
attribute value as an NCName
.prefix
attribute value is different from
null
, then validate
the prefix
attribute value as an NCName
.childNodes
list of n,
Text
or EntityReference
node, then it is an
xml-well-formedness-error
.EntityReference
node, then it is an
entity-error
.nodeName
attribute of n is
xml:space
@@ or {xml namespace}:space ?
and value
attribute of n is neither
default
nor preserve
, then it is an
xml-misc-error
.specified
,
manakaiAttributeType
(#ValueType Validity constraint: Attribute Value Type)value
of n.ID_ATTR
Name
. If it fails, then raise an
xml-validity-error
.ID
v is defined,
then raise an
xml-validity-error
.Name
. If it fails, then raise an
xml-validity-error
.ID
v is NOT
defined, then raise an
xml-validity-error
.Name
. If it fails, then raise an
xml-validity-error
.Entity
v is NOT
defined, then raise an
xml-validity-error
.Nmtoken
. If it fails, then raise an
xml-validity-error
.xml-validity-error
.xml-validity-error
.xml-validity-error
.AttributeDefinition
nodenodeName
attribute of n is
xml:space
@@ or {xml namespace}:space ?
and its declared type is different from (default|preserve),
(preserve|default), (default), or (preserve), then raise an
xml-misc-error
.childNodes
list of n,
Text
or EntityReference
node, then it is an
xml-well-formedness-error
.EntityReference
node, then it is an
entity-error
.NOTATION_ATTR
, enumerated values MUST
be declared. If not, then raise an
xml-validity-error
.NOTATION_ATTR
or ENUMERATED_ATTR
,
values MUST all be distinct. If not, then raise an
xml-validity-error
.NOTATION_ATTR
on an EMPTY
element, then raise an
xml-validity-error
.CDATASection
nodedata
attribute value as an XML character
data.data
attribute value contains
a string ]]>
, then raise an
xml-well-formedness-error
.childNodes
list of n contains
any nodes, they are in
xml-well-formedness-error
.Comment
noderound-trip-warning
.data
attribute value as an XML character
data.data
attribute value contains
a string --
, or if it ends with a character
-
, then raise an
xml-well-formedness-error
.childNodes
list of n contains
any nodes, they are in
xml-well-formedness-error
.Document
node1.0
or 1.1
,
then it is an unknown-error?
.xmlEncoding
attribute value does not
match to [A-Za-z] ([A-Za-z0-9._] | '-')*
@@ formal def, then it is an
xml-well-formedness-error
.childNodes
list of n have to
consist of zero or more Comment
and/or
ProcessingInstruction
nodes, followed by
an optional DocumentType
node, followed
by zero or more Comment
and/or
ProcessingInstruction
nodes, followed by
an Element
node, followed
by zero or more Comment
and/or
ProcessingInstruction
nodes. Any violation to this is an
xml-well-formedness-error
.childNodes
list of n,
EntityReference
node, then
check
nc recursively.allDeclarationsProcessed
DocumentFragment
nodechildNodes
list of n,
Element
, Text
, CDATASection
,
Comment
, ProcessingInstruction
, or
EntityReference
node, then it is an
xml-well-formedness-error
.EntityReference
node, then it is an
entity-error
.DocumentType
nodenodeName
attribute value as an NCName
.ownerDocument
attribute of n is
null
, then abort these substeps.documentElement
attribute of the node
set to ownerDocument
attribute of n is
null
, then abort these substeps.nodeName
attribute of the node set to
documentElement
attribute of the node set to
ownerDocument
attribute of n is
different from nodeName
of n,
then raise an
xml-validity-error
.publicId
attribute value as a public identifier.systemId
attribute value as a system identifier.publicId
attribute value of n is
not null
and the systemId
attribute
value of n is null
, then raise an
xml-well-formedness-error
.
@@ publicId == null? Or, publicId == ""childNodes
list of n,
ProcessingInstruction
node, then it is an
xml-well-formedness-error
.
@@ ref to manakai's extensionsentities
, notations
,
and elementTypes
lists of n,
check the
node recursively.NamedNodeMap
object in the entities
attribute of n does not contain Entity
nodes
whose nodeName
attribute are amp
,
lt
, gt
, apos
, and quot
then raise
xml-misc-recommendation
(s).
Element
nodelocalName
attribute value as an NCName
.prefix
attribute value is different from
null
, then validate
the prefix
attribute value as an NCName
.childNodes
list of n,
Element
,
Text
, CDATASection
, Comment
,
ProcessingInstruction
, or
EntityReference
node, then it is an
xml-well-formedness-error
.EntityReference
node, then it is an
entity-error
.attribute
attribute of n. Check conformance of attrs
as following:
Attr
node whose
nodeName
attribute value is equal to that of another
Attr
node in attrs, then raise an
xml-well-formedness-error
.ElementTypeDefinition
nodechildNodes
list of n contains
any nodes, they are in
xml-well-formedness-error
.At user option, an XML processor MAY issue a warning when a declaration mentions an element type for which no declaration is provided, but this is not an error.
For compatibility, it is an error if the content model allows an element to match more than one occurrence of an element type in the content model.
At user option, an XML processor MAY issue a warning if attributes are declared for an element type not itself declared, but this is not an error.
AttributeDefinition
node
with attribute type ID
in the
NamedNodeMap
list contained in the
attributeDefinitions
attribute of n, then raise an
xml-validity-error
.AttributeDefinition
node
with attribute type NOTATION
in the
NamedNodeMap
list contained in the
attributeDefinitions
attribute of n, then raise an
xml-validity-error
.Entity
node whose
notationName
attribute value is null
(i.e. a
parsed entity)entity-error
.nodeName
attribute value as an NCName
.publicId
attribute value as a public identifier.systemId
attribute value as a system identifier.publicId
attribute value of n is
not null
and the systemId
attribute
value of n is null
, then raise an
xml-well-formedness-error
.childNodes
list of n,
Element
,
Text
, CDATASection
, Comment
,
ProcessingInstruction
, or EntityReference
node, then it is an
xml-well-formedness-error
.EntityReference
node, then it is an
entity-error
.Entity
node whose
notationName
attribute value is not null
(i.e. an unparsed entity)nodeName
attribute value as an NCName
.publicId
attribute value as a public identifier.systemId
attribute value as a system identifier.systemId
attribute value of n is
null
, then raise an
xml-well-formedness-error
.notationName
attribute value of n as an
NCName
.childNodes
list of n contains
any nodes, they are in
xml-well-formedness-error
.EntityReference
nodeentity-error
.nodeName
attribute value as an NCName
.childNodes
list of n,
Element
,
Text
, CDATASection
, Comment
,
ProcessingInstruction
, or EntityReference
node, then it is an
xml-well-formedness-error
.EntityReference
node, then it is an
entity-error
.Notation
nodenodeName
attribute value as an NCName
.publicId
attribute value as a public identifier.systemId
attribute value as a system identifier.childNodes
list of n contains
any nodes, they are in
xml-well-formedness-error
.ProcessingInstruction
nodetarget
attribute value matches to the string
xml
in any case combination, then raise a
xml-well-formedness-error
.target
attribute value as an NCName
.data
attribute value as an XML character
data.data
attribute value contains a string
?>
, then raise a
xml-well-formedness-error
.data
attribute value starts with either
U+0009
CHARACTER
TABULATION
, U+000A
LINE
FEED
, U+000D
CARRIAGE
RETURN
, or U+0020
SPACE
character, then raise a
round-trip-error
.childNodes
list of n contains
any nodes, then raise an
xml-well-formedness-error
.Text
nodedata
attribute value as an XML character
data.childNodes
list of n contains
any nodes, they are in
xml-well-formedness-error
.This section defines a couple of character classes. These classes are referred to by algorithms specified above.
Character class Char10
contains the following characters:
U+0009
CHARACTER
TABULATION
U+000A
LINE FEED
U+000D
CARRIAGE
RETURN
U+0020
SPACE
.. U+D7FF
U+E000
.. U+FFFD
REPLACEMENT CHARACTER
U+10000
.. U+10FFFF
This character class contains all characters allowed in the production rule
Char
of XML 1.0
[XML10].
Character class CompatChar10
contains the following characters:
Document authors are encouraged to avoid "compatibility characters", as defined in section 6.8 of [Unicode @@ Unicode 2.0 @@] (see also D21 in section 3.6 of [Unicode3]).
Character class ControlChar10
contains the following characters:
U+007F
DELETE
..
U+0084
INDEX
U+0086
START OF SELECTED
AREA
.. U+009F
APPLICATION
PROGRAM COMMAND
U+FDD0
.. U+FDEF
U+1FFFE
.. U+1FFFF
U+2FFFE
.. U+2FFFF
U+3FFFE
.. U+3FFFF
U+4FFFE
.. U+4FFFF
U+5FFFE
.. U+5FFFF
U+6FFFE
.. U+6FFFF
U+7FFFE
.. U+7FFFF
U+8FFFE
.. U+8FFFF
U+9FFFE
.. U+9FFFF
U+AFFFE
.. U+AFFFF
U+BFFFE
.. U+BFFFF
U+CFFFE
.. U+CFFFF
U+DFFFE
.. U+DFFFF
U+EFFFE
.. U+EFFFF
U+FFFFE
.. U+FFFFF
U+10FFFE
.. U+10FFFF
This character class contains the characters listed in the Note in Section 2.2 of XML 1.0 [XML10], as amended by errata.
The character class NameStartChar10
contains the following characters:
This character class contains all characters allowed as the first character
of a string matching to the production rule
Name
of XML 1.0
[XML10].
The character class NameChar10
contains the following characters:
This character class contains all characters allowed as the second
character of a string matching to the production rule
Name
of XML 1.0
[XML10].
The character class PubidChar
contains the following characters:
U+0009
CHARACTER
TABULATION
U+000A
LINE FEED
U+000D
CARRIAGE
RETURN
U+0020
SPACE
U+0021
EXCLAMATION MARK
(!
)U+0023
DOLLAR SIGN
($
)U+0024
NUMBER SIGN
(#
)U+0025
PERCENT SIGN
(%
)U+0027
APOSTROPHE
('
)U+0028
LEFT PARENTHESIS
((
)U+0029
RIGHT
PARENTHESIS
()
)U+002A
ASTERISK
(*
)U+002B
PLUS SIGN
(+
)U+002C
COMMA
(,
)U+002D
HYPHEN-MINUS
(-
)U+002E
FULL STOP
(.
)U+002F
SOLIDUS
(/
)U+0030
DIGIT ZERO
(0
) .. U+0039
DIGIT NINE
(9
)U+003A
COLON
(:
)U+003B
SEMICOLON
(;
)U+003D
EQUAL SIGN
(=
)U+003F
QUESTION MARK
(?
)U+0040
COMMERCIAL AT
(@
)U+0041
LATIN CAPITAL LETTER
A
(A
) .. U+005A
LATIN CAPITAL LETTER Z
(Z
)U+005F
LOW LINE
(_
)U+0061
LATIN CAPITAL LETTER
A
(A
) .. U+007A
LATIN CAPITAL LETTER Z
(Z
)<http://www.w3.org/TR/xml>
.
This version of the specification is referenced.<http://www.w3.org/TR/CSS21>
.<http://dev.w3.org/csswg/cssom/Overview.html>
.<http://dev.w3.org/2006/webapi/selectors-api/Overview.html>
.
The latest published version of the specification is available at
<http://www.w3.org/TR/selectors-api/>
.<http://www.w3.org/TR/xbl/>
.