Enforce template type through static_assert

Question

I\'m trying to understand the usefulness of static_assert, and I want to know if it can help me in enforcing a design, and if so, how.

I have a general temp

Answer 1

I figured out a better solution for this problem by combining the answers and comments here.

I can define a static type checker like so:

template 
struct CheckTypes
{
    static const bool value = false;
};

template 
struct CheckTypes
{
    static const bool value = true;
};

Not sure if such a struct already exists in the standard library. Anyways, then in Foo, I can check for types and sizes using:

static_assert((sizeof(T) == sizeof(long) || sizeof(T) == sizeof(int)) && !CheckTypes::value, "Error!");