Re: [xsl] check the type of the $pattern argument to a regular expression?

[Abel Braaksma <abel.online@xxxxxxxxx>]

bryan rasmussen wrote:
> Is there a concise description somewhere as to how they differ, are
> there a large number of xslt regular expressions that are compatible
> with Java regular expressions or are they basically incompatible? I
> would suppose the main difference is that XSL-T regular expressions
> are Unicode compatible regex's  - correct?

I don't suppose there is such an overview. Some flavors are explained in 
Jeffrey Friedl's famous book and some are (briefly) explained here: 
http://regular-expressions.info. But they don't explain W3's favorite 
flavor (which is to a large part one-way compatible with Perl's flavor). 
You could check and compare the following:

XSLT / XPath regexes: http://www.w3.org/TR/xmlschema-2/#regexs and 
http://www.w3.org/TR/xpath-functions/#regex-syntax
Java regexes: 
http://java.sun.com/j2se/1.5.0/docs/api/java/util/regex/Pattern.html

The most obvious differences in syntax I found are the Java specific 
constructs, which are not covered in W3's flavor, like \p{javaLower} 
etc., possessive quantifiers, Quotation (\Q - \E), end/start of text (\A 
and \Z) and all special constructs (there is no look-ahead/look-behind, 
non-capturing parentheses, flags on/of in a group etc).

Cheers,
-- Abel Braaksma