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<TITLE>Canonical XML</TITLE>
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<H1>Canonical XML</H1>
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This document defines a subset of XML called canonical XML.
The intended use of canonical XML is in testing XML processors,
as a representation of the result of parsing an XML document.
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Every well-formed XML document has a unique structurally equivalent
canonical XML document. Two structurally equivalent XML
documents have a byte-for-byte identical canonical XML document.
Canonicalizing an XML document requires only information that an XML
processor is required to make available to an application.
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A canonical XML document conforms to the following grammar:
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CanonXML ::= Pi* element Pi*
element ::= Stag (Datachar | Pi | element)* Etag
Stag ::= '<' Name Atts '>'
Etag ::= '</' Name '>'
Pi ::= '<?' Name ' ' (((Char - S) Char*)? - (Char* '?>' Char*)) '?>'
Atts ::= (' ' Name '=' '"' Datachar* '"')*
Datachar ::= '&amp;' | '&lt;' | '&gt;' | '&quot;'
| '&#9;'| '&#10;'| '&#13;'
| (Char - ('&' | '<' | '>' | '"' | #x9 | #xA | #xD))
Name ::= (see XML spec)
Char ::= (see XML spec)
S ::= (see XML spec)
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Attributes are in lexicographical order (in Unicode bit order).
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A canonical XML document is encoded in UTF-8.
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Ignorable white space is considered significant and is treated equivalently
to data.
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<ADDRESS>
<A HREF="mailto:jjc@jclark.com">James Clark</A>
</ADDRESS>
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