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Re: [xsl] when to use 'as' attribute on a variable

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> So what advantage does document-node() give me over element(), node(), or 
> item()??

if the value of the variable is a document node (called a root node in
xpath 1) then typing it as document-node() will work, but declaring it
as element() would generate an error (as document nodes are not
elements). You could declare it as node() or item() and it would work
but essentially that's just turning off type checking, it's like
declaring everything in java to be Object; it's true, but loses most of
the benefits of having a type system. (Of course not everyone agrees
that having strict typing in XPath is a benefit, so XSLT is designed to
work pretty well if everything has such a general declared type (and that's
essentially the default behaviour if you don't declare types)


> In XPath 1 <xsl:value-of select="node()"/> would return the value of the 
> text nodes - presumably the node() you are referring to is a completely 
> different data type and unrelated?

node() in Xpath (1 and 2) is a node test and used in that context it
_selects_ any node. I'm not sure why you say "_text_ nodes" in the
above. node() matches all nodes (including text, elements, comments,
etc) this is unchanged in XPath 2.


Here we are talking about sequence types (as=".." attributes in xslt2)
although some of the syntax looks similar to XPath, the meaning is
completely different. This is most noticable for atomic types.
If you have select="xs:integer" then that is an XPath and selects
_element_ nodes, eg  <xs:integer/>. If on the other hand you have
as="xs:integer" that is specifying that the type of the value  being
declared is an _integer_, eg 10.

David

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