Question

Today I encountered strange bug in my application. I’ve tested it for like 2 hours and didn’t find a solution. Maybe you can help me solving this problem. So here it is:

#include <iostream>
#include <regex>
#include <vector>

int main()
{
        std::regex reg("rmvb|avi|rm|mp4|256");

        std::vector<std::string> ext{"rmvb", "avi", "rm", "mp4", "256", "null"};

        for (int i = 0; i < 6; i++)
        {
                std::cout << ext[i] << "\t" << std::boolalpha << std::regex_match(ext[i], reg) << std::endl;
        }

        return 0;
}

Output:

rmvb    true
avi true
rm  false
mp4 false
256 false
null    false

It seems that pattern is discarded after the second element – no matter what order I choose (I tried to swap them, because I thought that digits can cause this bug – but they aren’t). Now I have no idea what’s going on.

I’m using gcc version 4.6.3 (Debian 4.6.3-1).

Answer 1

The regex library is mostly not yet implemented in libstc++ (cf. status page). This may be a bug or just the result of it not being implemented. I’d suggest using Boost.Regex as a replacement.