相关疑难解决方法(0)

我试图在C++ 11代码中使用std :: regex,但看起来支持有点儿错误.一个例子:

#include <regex>
#include <iostream>

int main (int argc, const char * argv[]) {
    std::regex r("st|mt|tr");
    std::cerr << "st|mt|tr" << " matches st? " << std::regex_match("st", r) << std::endl;
    std::cerr << "st|mt|tr" << " matches mt? " << std::regex_match("mt", r) << std::endl;
    std::cerr << "st|mt|tr" << " matches tr? " << std::regex_match("tr", r) << std::endl;
}

输出:

st|mt|tr matches st? 1
st|mt|tr matches mt? 1
st|mt|tr matches tr? 0

当使用gcc(MacPorts gcc47 4.7.1_2)4.7.1编译时,使用

g++ *.cc -o test -std=c++11 …

为什么在g ++(Debian 4.6.3-1)4.6.3或clang version 3.2(trunk 159457)中找不到匹配项

#include <iostream>
#include <string>
#include <regex>

using namespace std;

int main()
{
    string line("test");
    regex pattern("test",regex_constants::grep);
    smatch result;

    bool ret(false);
    ret = regex_search(line,result,pattern);  
    cout <<  boolalpha << ret << endl;
    cout <<  result.size() << endl;
    return 0 ;
}

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