Re: Algorithm for merging the pattern facets in a base simpleType with a subtype? from Michael Kay on 2011-04-22 (xmlschema-dev@w3.org from April 2011)

From: Michael Kay <mike@saxonica.com>
Date: Fri, 22 Apr 2011 18:13:48 +0100
To: xmlschema-dev@w3.org
Message-ID: <4DB1B74C.9050205@saxonica.com>

> Since regular languages are closed under intersection,
> the result of a logical 'and' of two regexes is a regular
> language. And it will have an expression using XSD regular
> expressions.

Interesting. Is there a general algorithm for deriving that expression? 
In the absence of the "&&" and lookahead operators, it doesn't seem easy.

Michael Kay
Saxonica

Received on Friday, 22 April 2011 17:14:08 UTC