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Bug 29855 - [FO31] Non-capturing subexpressions
Summary: [FO31] Non-capturing subexpressions
Alias: None
Product: XPath / XQuery / XSLT
Classification: Unclassified
Component: Functions and Operators 3.1 (show other bugs)
Version: Candidate Recommendation
Hardware: PC All
: P2 minor
Target Milestone: ---
Assignee: Michael Kay
QA Contact: Mailing list for public feedback on specs from XSL and XML Query WGs
Depends on:
Reported: 2016-09-21 20:16 UTC by Michael Kay
Modified: 2016-12-16 19:55 UTC (History)
1 user (show)

See Also:


Description Michael Kay 2016-09-21 20:16:41 UTC
The F+O spec states in 5.6.1:

The presence of the optional ?: has no effect on the set of strings that match the regular expression

This is not strictly true. In the presence of back-references it can index change the set of strings that match the regex.

I am fixing this by adding "In the absence of back-references (see below), " to the start of the sentence.
Comment 1 Andrew Coleman 2016-09-27 15:47:47 UTC
The WG agrees
Comment 2 Michael Kay 2016-09-27 21:00:26 UTC
The changes had already been applied to the spec.