Re: [Patch] First step towards fast parsing of float types

[Martin Sebor <sebor at roguewave dot com>]

Paolo Carlini wrote:

> Hi,
>
> this tiny step only clarifies a bit the logic in some (corner)
> cases and adds missing testcases. Basically, we were accepting
> thousands separators and decimal point also *after* 'e'/'E'.

FWIW, your (i.e., libstdc++) handling of thousands_sep and
decimal_point is off in one other respect as well. Stage 2
specifies that these special characters be processed _prior_
to any digits. Libstdc++ process them _after_. A super-
pedantic test case is below ;-)

Best
Martin


#include <locale>
#include <sstream>

int main ()
{
    struct Punct: std::numpunct<char> {
        std::string do_grouping () const { return "\1"; }
        char do_thousands_sep () const { return '2'; }
        char do_decimal_point () const { return '4'; }
    };

    std::stringstream strm ("1234");

    strm.imbue (std::locale (strm.getloc (), (std::numpunct<char>*)new 
Punct));

    double d = 0;

    strm >> d;

    return !(13.0 == d && (std::ios::eofbit == strm.rdstate ()));
}