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Re: What's an "XML Fragment"?

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At 01:06 PM 10/08/2000 -0700, Elliotte Rusty Harold wrote:

Section 13 of the XSLT specification, Messages, makes references to an
"XML fragment" data type that is mentioned nowhere else in the spec.
Specifically,

"The xsl:message is instantiated by instantiating the content to create
an XML fragment. This XML fragment is the content of the message."

I'm 90% certain that what's meant here is what is elsewhere called a
"result tree fragment". Can anybody confirm or deny that? In any case,
this seems to need an erratum to clarify the point.

I have no inside information, obviously, but I just read that as a reference to XML fragments as defined by the apparently moribund XML Fragment Interchange WD (last updated 6/30/99). Although nothing seems to be happening with that WD, it was still fairly current as of the time the XSLT WD went to Recommendation.

See:
   http://www.w3.org/TR/WD-xml-fragment#terminology
Particularly this:

   fragment: A general term to refer to part of an XML document,
   plus possibly some extra information, that may be useful to
   use and interchange in the absence of the rest of the XML
   document. See the rest of the fragment-related terms when a
   more precise definition is required.

Among the "rest of the fragment-related terms" is this one:

   fragment body: A well-balanced region of an XML document being
   considered as (logically and/or physically) separate from the
   rest of the document for the purposes of defining it as a
   fragment. Also, that part of a fragment entity that consists
   solely of the well-balanced region from the complete XML document.

The definition of "well-balanced" says:

   A region (consecutive sequence of characters) of an XML document
   is said to be (well-)balanced if it matches production [43]
   content of XML 1.0. Informally this means that, if the region
   includes any part of the markup of any construct, it contains
   all of the markup of that construct (e.g., in the case of
   elements, all of both the start and end tag)

So a well-balanced fragment might look like this:

   <element>...</element>
   <element>...</element>

even though it's not well-*formed* (i.e. lacks a root element). I think this is how Mike Kay's book defines well-balanced, too, although I don't recall his referring to the Fragment Interchange WD.

Just a guess!

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