* include/Makefile.am: Add regex.tcc.
* include/Makefile.in: Regenerate.
* include/bits/regex.h: Remove definitions to regex.tcc.
* include/bits/regex.tcc: New.
(match_results::format, regex_replace): Implement;
* include/bits/regex_compiler.h: Move _M_flags to the top of class
member list, because other members' initialization depend on it.
* include/bits/regex_compiler.tcc
(_Compiler<>::_Compiler): Adjust member initializations.
(_Compiler<>::_M_quantifier): Fix ungreedy interval quantifier.
* include/bits/regex_executor.h: Remove _RegexT from _*Executor classes.
In the future, all regex classes may refactor to *Impl style.
* include/bits/regex_executor.tcc (_Executor::_M_set_results):
Merge identical code from _*Executor classes.
* testsuite/28_regex/algorithms/regex_match/extended/
string_dispatch_01.cc (fake_match<>): Adjust the hacking-style testcase
caller for new __get_executors interface.
* testsuite/28_regex/algorithms/regex_replace/char/basic_replace.cc:
New.
* testsuite/28_regex/match_results/format.cc: New.
* testsuite/28_regex/traits/char/lookup_collatename.cc: Remove digraph
testcase.
* testsuite/28_regex/traits/wchar_t/lookup_collatename.cc: Likewise.