How do I check if a template parameter is a power of two?

Question

I want to create a structure that allocates statically an array of 2^N bytes, but I don\'t want the users of this structure to specify this size as the exponent

Answer 1

You can use static_assert to provide an error message:

template
struct is_power_of_two {
    static_assert((N > 1) & !(N & (N - 1)), "Template parameter must be a power of two.");
};