How to check if a class has a specific overload for member x?

[Hipreme via Digitalmars-d-learn]

I wish to generate some functions using mixin template and I wish 
to check if the current class already has an specific overload 
with parameters (A, B).

What I'm currently trying is doing `__traits(getOverloads, T, 
"foo")`, and then checking if its type are equal. But it seems 
hackish, and I would like to make something like 
`hasOverload!(Test, "foo", int(int a, int b) const)` or something 
like that.