Re: [xsl] XSLT result tree fragment, with XSLT 3.0 and xsl:variable

["G. Ken Holman g.ken.holman@xxxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>]

Mukul, my pedantic concerns about your text here
relate to the distinction between nodes and XML syntax.

XSLT 1.0 result tree fragments were exactly that:
fragments of the result tree of nodes ... that
happen to be serialized as XML syntax if the user
intended to create XML syntax. But XSLT guides
the creation of result tree nodes from source
tree nodes based on stylesheet tree nodes. If the
XSLT is an intermediate step of the manipulation
of trees of content, then XML syntax doesn't come into play.

XML only comes out if the result tree is
serialized as XML (and there are other choices,
as you know, for serialization syntax).

So when you say:

> It seems to me that, XSLT 1.0's "result tree fragment" (before
> being serialized to the output XML) is a well-formed XML fragment.

... I don't agree it is a well-formed XML
fragment. It is a fragment of a node tree, so a
bunch of nodes, which can be serialized as XML
syntax, and that serialization ensures each XML element node is well-formed.

If in the completed result tree there are zero or
more than one apex element nodes, the tree is
serialized as an external XML entity. If there is
one apex element node in the fragment, it is serialized as an XML document.

So my counsel is to reflect in your text that the
languages are creating sequences of nodes to be
serialized and that XML only happens if
serialization is engaged and is engaged requesting XML syntax.

I hope this is helpful.

At 2023-04-10 11:42 +0000, you wrote:
> Hi all,
> B  B While comparing the, data models of XPath
> 1.0 and 3.1 languages (in the context of XSLT
> transformations), I noticed that, XSLT 3.0
> doesn't have (i.e, it doesn't define) a data
> type named as "result tree fragment" Whereas,
> the data type "result tree fragment" is available with XSLT 1.0.
>
> With respect to this topic, I've been comparing
> the semantics of XSLT xsl:variable instruction
> within 1.0 and 3.0 versions of XSLT language.
>
> 1) From the XSLT 1.0 spec
> A variable is a name that may be bound to a
> value. The value to which a variable is bound
> (the value of the variable) can be an object of
> any of the types that can be returned by expressions.
> There is a region of the stylesheet tree within which the binding is
visible.
> Result Tree Fragments
> Variables introduce an additional data-type into
> the expression language. This additional data
> type is called result tree fragment. A variable
> may be bound to a result tree fragment instead
> of one of the four basic XPath data-types
> (string, number, boolean, node-set). A result
> tree fragment represents a fragment of the result tree.
>
> 2) From the XSLT 3.0 spec
> The value of the variable is computed using the
> expression given in the select attribute or the contained sequence
constructor.
> I think, from the point of view of XSLT language
> in general, "result tree fragment" (from XSLT
> 1.0) and "sequence constructor" (from XSLT 3.0)
> both serialize into the XSLT transformation'sB
> output (which typically would be XML for this
> discussion). The XSLT 3.0 sequence constructor,
> shall result in a value with a XPath 3.1 data
> type item()+. The XSLT 3.0 language, defines
> "sequence constructor" as : A sequence
> constructor is a sequence of zero or more
> sibling nodes in the stylesheet that can be
> evaluated to return a sequence of nodes, atomic values, and function items.
>
> It seems to me that, XSLT 1.0's "result tree
> fragment" (before being serialized to the output
> XML) is a well-formed XML fragment. Whereas,
> XSLT 3.0's sequence constructor is also a
> well-formed XML fragment, that evaluates to a
> sequence of nodes, atomic values, and function
> items. Other than, the XPath 3.1 function items
> (which is not available with XSLT 1.0/XPath
> 1.0), XSLT 3.0's sequence of nodes and atomic
> values looks to me, an intermediate compiler
> representation that is finally transformed into
> the XML document available as a result of XSLT transformation.
>
> Any thoughts about this topic, shall be useful to know.
>
>
> --
> Regards,
> Mukul Gandhi
> <http://www.mulberrytech.com/xsl/xsl-list>XSL-List info and archive
> <http://lists.mulberrytech.com/unsub/xsl-list/96802>EasyUnsubscribe
> (<>by email)


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