[cmake-developers] [CMake 0013792]: REGEX REPLACE fails if () capture is empty

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://public.kitware.com/Bug/view.php?id=13792 
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Reported By:                mwoehlke
Assigned To:                
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Project:                    CMake
Issue ID:                   13792
Category:                   CMake
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
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Date Submitted:             2012-12-13 16:26 EST
Last Modified:              2012-12-13 16:26 EST
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Summary:                    REGEX REPLACE fails if () capture is empty
Description: 
string(REGEX REPLACE) fails for certain patterns with 'matched an empty string'
error if a capture grood is empty, even if the full match is non-empty.

Steps to Reproduce: 
set(input foo)
string(REGEX REPLACE "^([^.]*)(\\..*)?$" "\\1" output ${input})

Additional Information: 
CMake is correctly matching the regular expression (as can be seen by examining
the captures), and the overall pattern (which is the old text to be replaced) is
non-empty, so there should be no problem. (Even more interestingly, while the
above pattern triggers the problem, other patterns which one might expect to
tickle the same glitch do not.)
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Issue History 
Date Modified    Username       Field                    Change               
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2012-12-13 16:26 mwoehlke       New Issue                                    
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