[Patch] regex bracket expression implementaion

[Tim Shen]

Fully tested under x86_64. (make bootstrap && make -k check).

Next, I'll try to refactor _Grep_matcher using templates instead of
virtual functions, to make implementing back-reference easier.

Thanks!


-- 
Tim Shen
-------------- next part --------------
A non-text attachment was scrubbed...
Name: bracket.patch
Type: application/octet-stream
Size: 27339 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/libstdc++/attachments/20130801/b89cab27/attachment.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: changelog
Type: application/octet-stream
Size: 507 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/libstdc++/attachments/20130801/b89cab27/attachment-0001.obj>