"Oleg A. Paraschenko" <olpa@x...> wrote in message 
20050901234512.0967075d.olpa@x...">news:20050901234512.0967075d.olpa@x......
>  Hello,
>
>  do you know the dark corners of XSLT? Here is one. Compare two
> variables:
>
> <xsl:variable name="v1" select="some-xpath"/>
> <xsl:variable name="v2"><xsl:copy-of select="some-xpath"/></xsl:variable>
>
>  Are "v1" and "v2" the same? I mean: can "v1" and "v2" be used in a
> program interchangeably? Answers:
>
> 1) yes
> 2) no
> 3) implementation-dependant


This is something fundamental and not a dark corner at all.

This is an XSLT FAQ  asked for very frequently in the xsl-list where such 
questions must be directed to.

As defined above, the value of "v1" is of type node-set, while the value of 
"v2" is of type RTF (in XSLT 1.0) or document node (in XSLT 2.0).


There are excellent books by Michael Kay and Jeni Tennison on XSLT (1.0 and 
2.0) and XPath (1.0 and 2.0), which cover in details such questions.

Also, the XSLT FAQ of David Pawson is another great place to look at.


Cheers,
Dimitre Novatchev.