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Bug 2718 - Non-capturing sub-expressions
Summary: Non-capturing sub-expressions
Alias: None
Product: XPath / XQuery / XSLT
Classification: Unclassified
Component: Functions and Operators 1.0 (show other bugs)
Version: Last Call drafts
Hardware: PC Windows XP
: P2 normal
Target Milestone: ---
Assignee: Ashok Malhotra
QA Contact: Mailing list for public feedback on specs from XSL and XML Query WGs
Depends on:
Reported: 2006-01-15 19:30 UTC by Ashok Malhotra
Modified: 2006-11-16 18:52 UTC (History)
1 user (show)

See Also:


Description Ashok Malhotra 2006-01-15 19:30:06 UTC extends the semantics
of the regular expressions defined in XML Schema 1.0 to allow for capture
buffers; I would like to re-use regular expressions as de- fined in the
candidate recommendation in a DTLL-like format, but an imporant requirement is
automatic assignment of names for the captured substrings based on the index
number of the parenthesized sub-expression as defined in the technical report.

This is not feasible however with the current syntax as it does not allow
non-capturing sub-expressions, so I would have to further extend the format
which makes sharing of regular expressions and regex engines difficult. In fact,
in order to re-use regular expressions as found on many web sites and programs,
and as produced by many tools, one would first have to re-write them to fit into
this model.

I thus think the regular expression syntax should further be extended to allow
for non-capturing sub-expressions using a syntax like (?:...) as is available in
most other regular expression formats.

Björn Höhrmann · · Weinh.
Str. 22 · Telefon: +49(0)621/4309674 ·
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Comment 1 Ashok Malhotra 2006-01-20 16:20:57 UTC
Created in wrong bucket.  Closing here and opening in CR comments.