[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message]

RE: XSLT and XQuery

• To: "'James Clark'" <jjc@j...>,<michael.h.kay@n...>,"'Jonathan Borden'" <jborden@m...>,"'David Carlisle'" <davidc@n...>,"'Jonathan Robie'" <jonathan.robie@s...>
• Subject: RE: XSLT and XQuery
• From: "Michael Kay" <michael.h.kay@n...>
• Date: Fri, 4 Jan 2002 11:31:22 -0000
• Cc: <www-xml-query-comments@w...>,<xml-dev@l...>
• Importance: Normal
• In-reply-to: <014001c19510$a4a8dd30$0e00a8c0@b...>
• Reply-to: <michael.h.kay@n...>

> Template rules are just syntactic sugar for a recursive
> function call and a
> case statement, both of which XQuery has (doesn't it?).

Technically true, but there are many cases where you would naturally use
template rules in XSLT where you wouldn't naturally use a recursive function
call and a case statement in XQuery. I guess the open question is, can
template rules be optimized if you have sufficient a priori knowledge of the
schema?

> I  would be inclined
> to nominate some of the axes (almost everything but children and
> descendants) as the prime things to exclude from XQuery, both
> because they
> are hard to optimize and hard to statically type in any sort
> of useful way.

Now I can reverse the argument: surely most of the axes are just syntactic
sugar for a recursive function call? And using the ancestor axis (for
example) explicitly is surely both more convenient for the user, and easier
to optimize, than a recursive call on a getParent() function?

Also, I've never understood why the descendant axis is supposedly easier to
statically type than the ancestor axis.

Mike Kay

• Follow-Ups:
  • Re: XSLT and XQuery
    • From: "James Clark" <jjc@j...>

• References:
  • Re: XSLT and XQuery
    • From: "James Clark" <jjc@j...>

• Prev by Date: Re: XSLT and XQuery
• Next by Date: Re: The use of XML syntax in XML Query
• Previous by thread: Re: XSLT and XQuery
• Next by thread: Re: XSLT and XQuery
• Index(es):
  • Date
  • Thread