RE: [XQuery 1.0 and XPath 2.0 Functions and Operators]

> 
> 
> > would suggest that substring-before($s1, $s2) is defined as:
> ...
> I don't understand the rational of using XSLT specific 
> definitions for string matching if it has already has been 
> defined by common Unicode specs.

I think the rationale is:

Firstly, we aren't insisting that all collations use the Unicode
collation algorithm.

Secondly, the Unicode TR is not rigorous enough. The "Searching" section
is labeled as "informative", and it's written in the style of a
discussion of options and possibilities, not a specification that
products can conform to.

However, we have been guided in writing these specifications by the
Unicode work (which has gone on in parallel - it wasn't all there when
we started) and this should continue. We could also probably align the
terminology better - I think our collation units are probably the same
thing as Unicode's collation elements (though perhaps we avoided
"elements" as being a reserved word).


> 
> >I think the rules for starts-with, contains, and ends-with are 
> >unambiguous
> I think they are ambiguous  starts-with("-a", " a") true a false?
> 

Sorry, I meant that the rules were unambiguous given the existence of a
function that maps a sequence of characters to a sequence of collation
units (which is what the collation provides).

Michael Kay

Received on Tuesday, 13 January 2004 18:19:01 UTC