Is even or odd in C++ template metaprogramming.

README.md

Is even or odd?

This is a common exercise implemented in C++11 using template metaprogramming techniques.

Compiling

Just run make in your shell :p

Main.cc

#include <iostream>

template <int a>
struct isodd {
    static constexpr bool value = a % 2;
};

template <int a>
struct iseven {
    static constexpr bool value = !(a % 2);
};

template <int a>
struct square {
    static constexpr int value = a * a;
};

int main() {
    auto r1 = iseven< square< 4 >::value >::value;
    auto r2 = isodd< square< 3 >::value >::value;

    std::cout << r1 << std::endl;
    std::cout << r1 << std::endl;
    return 0;
}

Makefile

all:
	g++ Main.cc -o isodd -std=c++11

Why not just
template constexpr int square(){return a *a };
template constexpr bool isodd(){return a % 2 ==1;};
static_assert(isodd<square<4>>,"16 isnt squre?")
Seems much more natural...

well atleast after the markdown is removed...