RE: Casting: Use Cases VS Specs

Steve:
There is an open issue on whether we allow constructors to take
expressions as arguments.  If we decide that we do, then the use case
would work fine.
Otherwise it would have to be changed to "cast as decimal($p/text())".

Please note that the documents you are looking at are works in process
and are likely to change.  Even though the editors make their best
efforts the specs will sometimes have inconsistencies.  Our apologies.


All the best, Ashok 
===========================================================
Ashok Malhotra              <mailto: ashokma@microsoft.com> 
Microsoft Corporation
212 Hessian Hills Road
Croton-On-Hudson, NY 10520 USA 
Redmond: 425-703-9462                New York: 914-271-6477 



-----Original Message-----
From: Steve Sullivan [mailto:sullivan@Mathcom.COM] 
Sent: Friday, March 08, 2002 9:28 AM
To: www-ql@w3.org
Subject: Casting: Use Cases VS Specs


Hi,

There appears to be a mismatch between the XML Query Use Cases
and the Functions and Operators specs.

In the XML Query Use Cases W3C Working Draft 20 December 2001,
section 1.1.9.10 Q10, the example is:
    <results>
    {
        let $doc := document("prices.xml")
        for $t in distinct-values($doc//book/title)
        let $p := $doc//book[title = $t]/price
        return
          <minprice title={ $t/text() }>
    <price>{ min(decimal($p/text())) }</price>
    </minprice>
    }
    </results>

The expression "min(decimal($p/text()))" implies that the
cast decimal() can be applied to a sequence.

Yet nowhere in "XQuery 1.0 and XPath 2.0 Functions and Operators
W3C Working Draft 20 December 2001" is there such as cast.

Section 3.2.1 discusses a decimal() constructor that takes
a single string literal.
Section 14 discusses casting functions from primitives to primitives,
but not over sequences.

The intent of the use case is clear ... apparently the cast
should be applied to each element of the sequence.
But where is it in the specs?

Thanks,

Steve


========================================
Steve Sullivan    sullivan@mathcom.com

   Mathcom Solutions: Custom Software Development.
    * XML, XQuery, XSLT, Java, JDBC, J2EE, JSP, JNI, ...
    * Mathematical optimization, simulation, and modeling.

http://www.mathcom.com    303-494-7115
========================================

Received on Friday, 8 March 2002 12:53:13 UTC