Using std::extent on std::array

Question

I have a templatized function and I want to static_assert that it\'s type has a size of three. This code illustrates what I\'m trying to do, but doesn\'t work:<

Answer 1

This builds on iavr's solution.

template < typename T >
void foo( T& param )
{
    static_assert( 3 == ( std::is_array< T >::value ? std::extent< T >::value : std::tuple_size< T >::value ), "param must have a size of 3" );
}