Extract C++ template parameters

Question

Although I\'m doubtful, I\'m curious as to whether it\'s possible to extract primitive-type template parameters from an existing type, perhaps using RTTI.

For exampl

Answer 1

As stated by other answers, for std::bitset you can get the size by using the size() member function, which should be the right choice, better than any other trick.

There were several proposals for the generic case, almost similar to the one I suggest below, but still I think this one is simpler:

template  typename T, std::size_t K>
auto extractSize(const T&) {
    return K;
}

int main() {
    std::bitset<6> f1;
    std::bitset<13> f2;
    std::cout << extractSize(f1) << std::endl;
    std::cout << extractSize(f2) << std::endl;
}