W3C home > Mailing lists > Public > public-qt-comments@w3.org > July 2013

[Bug 22732] [F+O 3.0] Function-lookup and the dynamic context

From: <bugzilla@jessica.w3.org>
Date: Fri, 19 Jul 2013 13:08:53 +0000
To: public-qt-comments@w3.org
Message-ID: <bug-22732-523-g46yDno4mL@http.www.w3.org/Bugs/Public/>
https://www.w3.org/Bugs/Public/show_bug.cgi?id=22732

--- Comment #3 from Michael Kay <mike@saxonica.com> ---
Perhaps the reason this is a Note in F+O is that the definitive rules are in
the language book, specifically 

3.1.5.1 Evaluating Static and Dynamic Function Calls

This makes it fairly clear that there is a distinction between built-in
functions and user-defined functions, and that only the first kind carry
context information around with them: so it's broadly along the lines of the
proposal in comment #2.

This leaves a few relatively minor problems to be fixed:

(a) the Note in F+O function-lookup() is a poor summary of the situation; it
should refer to 3.1.5.1 in the language book. 

(b) the semantics in the language book rely on a built-in function item
carrying context information around with it, and the spec for function-lookup()
needs to say normatively how this is derived (viz from the context of the call
to function-lookup().

(c) the rules in both the XQuery and XPath language books distinguish the two
kinds of function according to whether the implementation of the function is a
"FunctionBody", which doesn't allow for user-defined functions to be written in
a different host language (such as XSLT). Perhaps the XPath version should say
"FunctionBody, or its equivalent in the some other host language". Or perhaps
the XSLT book should say that xsl:function defines a function whose
implementation is "a FunctionBody with equivalent semantics to the sequence
constructor contained in the xsl:function declaration".

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
Received on Friday, 19 July 2013 13:08:54 UTC

This archive was generated by hypermail 2.3.1 : Wednesday, 7 January 2015 15:45:53 UTC