W3C home > Mailing lists > Public > public-qt-comments@w3.org > October 2012

[Bug 19504] [QT3TS] instanceof139

From: <bugzilla@jessica.w3.org>
Date: Sat, 13 Oct 2012 19:17:11 +0000
To: public-qt-comments@w3.org
Message-ID: <bug-19504-523-Xe9Aflczrb@http.www.w3.org/Bugs/Public/>
https://www.w3.org/Bugs/Public/show_bug.cgi?id=19504

--- Comment #9 from Tim Mills <tim@cbcl.co.uk> ---
(In reply to comment #6)
> There are plenty of other cases where the extent of a type P is clearly a
> subset of the extent of another type S, but P is not substitutable for S.
> For example, the pair (P=xs:unsignedByte, S=xs:int), or the pair
> (P=string(length<5), S=string(length<10)) Agreed, this situation is
> undesirable (and in the case of the integer subtypes, makes them fairly
> unusable), but it's a consequence of the original decision to go with "named
> typing" and I think we have to live with it.

To be clear, the 'matches' judgement does not hold for the sort of pairings you
are describing here.  The unsigned byte value B does not match xs:int. 
However, it does hold that all values which match union(P,Q) also match
union(P,Q,R).

I am increasingly convinced that the decision made for XSD doesn't make a great
deal of sense for XQuery.

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
Received on Saturday, 13 October 2012 19:17:13 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Saturday, 13 October 2012 19:17:13 GMT