Is there any behaviour of use-attribute sets that isn't more easily
achievable using normal variables?
I've used xslt probably most days since the first working drafts and
I've _never_ once found any use for this feature.
Unlike a global variable, the result of expanding an attribute set can
be different on different occasions - the result can depend on the
context node. So they are more like a restricted kind of
xsl:call-template with no parameters than like global variables.
But I can't think of anything that attribute sets can do that
call-template can't do just as easily. In my view they are historic.
Attribute sets were in the first published working draft of XSLT 1.0
(Aug 1988, http://www.w3.org/TR/1998/WD-xsl-19980818) but named
templates were only introduced later (April 1999,
http://www.w3.org/TR/1999/WD-xslt-19990421) having evolved from an
earlier facility - macros (Dec 1998,
http://www.w3.org/TR/1998/WD-xsl-19981216).
I might be wrong, but I suspect this was part of the "should XSLT be a
general-purpose programming language?" debate. Named templates are
clearly a general-purpose programming construct, whereas attribute-sets
were designed specifically to emulate features in cascading stylesheets.
In the end, in my view, general purpose programming constructs always
win over special-purpose constructs.
Michael Kay
XSL-List info and archive: http://www.mulberrytech.com/xsl/xsl-list