Regex C Help on escape character

Question

I am having trouble extracting the token values from my string : "JOIN #ROOM\r\n" I am compiling my code on Mingw64 with the following arguments : g++ tregex.cpp -o tregex.exe -std=gnu++11

I get this error , but not my exception for some reason :

This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information. terminate called after throwing an instance of 'std::regex_error' what(): regex_error

This is my code :

#include <regex>
#include <string>
#include <iostream>
using namespace std;

//Tregex.cpp

int main(void) {
    regex rgx("[[:cntrl:]]");
    string str = "JOIN  #ROOM\r\n";
    smatch match;
    try{
        if(regex_search(str, match, rgx))
            for(auto token:match) cout << token <<"\n";
        cout<< endl;
    }
    catch(regex_error & e){
        if( e.code() == regex_constants::error_escape )
            cerr << "invalid escape character \n";
        else if( e.code() == regex_constants::error_stack )
            cerr << "regular expression is not big enough\n";
        else
            cerr << "exception caught: "<< e.what()<<"\n";
    }
    cin.get();
    return 0;
}

`` support in gcc is [far from complete](http://stackoverflow.com/questions/12530406/is-gcc4-7-buggy-about-regular-expressions/12665408#12665408). You should switch over to using Boost if you need regex. — Praetorian, Jun 05 '13 at 20:49
Wow, I didn't even know that regex was still in crude form for gcc. So, is the visual studio compiler for windows fully implemented? I'll stick with using boost then. — HeroofCode, Jun 05 '13 at 22:11
@HeroofCode Visual Studio 2012 does support regex, but it is lacking several other C++11 language features. — Praetorian, Jun 06 '13 at 01:56
@HappyGreenKidNaps [Yes](https://en.wikipedia.org/wiki/C%2B%2B_Technical_Report_1#Regular_expressions) — Praetorian, Jun 25 '13 at 23:05

score 0 · Answer 1 · edited May 23 '17 at 10:25

0

FWIW, there's nothing wrong with your C++ code, and it works perfectly using Clang and libc++ on my MacBook.

As indicated by the comments above, <regex> is one of the features that works in the LLVM project's libc++ but has never worked properly in the GNU project's libstdc++. You might try switching to libc++ if it's available for your platform.

edited May 23 '17 at 10:25

Community

1
1

answered Jun 25 '13 at 22:29

Quuxplusone

23,928
8
94
159

Regex C Help on escape character

1 Answers1