How do I use boost::lexical_cast and std::boolalpha? i.e. boost::lexical_cast< bool>(“true”)

Question

I\'ve seen some answers to other boost::lexical_cast questions that assert the following is possible:

bool b = boost::lexical_cast< bool >         


        

Answer 1

In addition to the answer form poindexter, you can wrap the method from here in a specialized version of boost::lexical_cast:

namespace boost {
    template<> 
    bool lexical_cast(const std::string& arg) {
        std::istringstream ss(arg);
        bool b;
        ss >> std::boolalpha >> b;
        return b;
    }

    template<>
    std::string lexical_cast(const bool& b) {
        std::ostringstream ss;
        ss << std::boolalpha << b;
        return ss.str();
    }
}

And use it:

#include 
#include 

//... specializations

int main() {
    bool b = boost::lexical_cast(std::string("true"));
    std::cout << std::boolalpha << b << std::endl;
    std::string txt = boost::lexical_cast< std::string >(b);
    std::cout << txt << std::endl;

    return 0;
}

I personally liked this approach because it hides any special code (e.g. using LocaleBool or to_bool(...) from the link) for converting to/from bools.