lookahead fails to compile, when utf8 strings are used #338
Description
we use a small regex to check, if the string for the password is at least 8 chars, and includes at least one special char.
"^(?=.?[.<>()+\-&?;,%:"\\='])[[:alnum:][:punct:]À-ž]{8,}$"
this is working fine - as long as ascii chars are involved - as soon as we need to include german umlaut in utf8, we tried changing to the u8 string version.
EXPECT_TRUE(ctre::match<u8"[[:alnum:][:punct:]À-ž]+">(u8"Günter&Kastenfrosch"));
and this would work - but the positive lookahead, which checks for the special chars
-> this is not compiling
EXPECT_TRUE(ctre::match<u8"^(?=.*?[.<>()+\\-&?*;,%:\"\\\\='])[[:alnum:][:punct:]À-ž]{8,}$">(u8"Günter&Kastenfrosch"));
(tried with MSVC 17.12.4, with standard at c++23 )
error would be in
evaluation.hpp(143)
ctre::evaluate<R,BeginIterator,Iterator,EndIterator,ctre::set<ctre::character<46>,ctre::character<60>,ctre::character<62>,ctre::character<40>,ctre::character<41>,ctre::character<43>,ctre::character<45>,ctre::character<38>,ctre::character<63>,ctre::character<42>,ctre::character<59>,ctre::character<44>,ctre::character<37>,ctre::character<58>,ctre::character<34>,ctre::character<92>,ctre::character<61>,ctre::character<39>>,ctre::end_lookahead_mark,void>(const BeginIterator,Iterator,const EndIterator,const ctre::flags &,R,ctll::list<ctre::set<ctre::character<46>,ctre::character<60>,ctre::character<62>,ctre::character<40>,ctre::character<41>,ctre::character<43>,ctre::character<45>,ctre::character<38>,ctre::character<63>,ctre::character<42>,ctre::character<59>,ctre::character<44>,ctre::character<37>,ctre::character<58>,ctre::character<34>,ctre::character<92>,ctre::character<61>,ctre::character<39>>,ctre::end_lookahead_mark> with [ R=ctre::regex_results<ctre::match_method::exec::result_iterator>, BeginIterator=ctre::utf8_iterator, Iterator=ctre::match_method::exec::result_iterator, EndIterator=ctre::utf8_iterator::sentinel ]
by the way
std::string g{ "Günter" };
std::u8string u8s_from_string(g.cbegin(), g.cend());
EXPECT_TRUE(ctre::match<u8"[[:alnum:][:punct:]À-ž]+">(u8s_from_string));
EXPECT_TRUE(ctre::match<u8"[[:alnum:][:punct:]À-ž]+">(u8s_from_string.c_str()));
the first one fails, the second one works - and I don't get why.... but it compiles