C++ output operators for std::array and std::tuple

ostream-helpers.h

#pragma once

#include <array>
#include <tuple>
#include <iostream>

// use this namespace to expose operators
namespace ostream_helpers {

namespace {

template< typename T, std::size_t Dim, std::size_t... Is >
void cout_helper( std::ostream& os, const std::array<T,Dim>& in, std::index_sequence<Is...> ){
    static_assert( sizeof...(Is) == Dim );
    ( void( os << std::get<Is>(in) << (Is == sizeof...(Is)-1 ? "" : ", ")), ... );
}

template< typename... Ts, std::size_t... Is >
void cout_helper( std::ostream& os, const std::tuple<Ts...>& in, std::index_sequence<Is...> ){
    static_assert( sizeof...(Ts) == sizeof...(Is) );
    ( void(os << std::get<Is>(in) << (Is == sizeof...(Is)-1 ? "" : ", ")), ... );
}

}

template< typename... Ts >
std::ostream& operator<<( std::ostream& os, const std::tuple<Ts...>& in ){
    cout_helper( os, in, std::make_index_sequence<sizeof...(Ts)>() );
    return os;
}

template< typename T, std::size_t Dim >
std::ostream& operator<<( std::ostream& os, const std::array<T,Dim>& in ){
    cout_helper( os, in, std::make_index_sequence<Dim>() );
    return os;
}

};