Use different impl when the type parameters are the same

I have an impl with two generic typenum parameters. The impl's function should return a different type when the parameters are the same. (The different type is a more compact representation that can only be realized when the type parameters are the s

Combine an integer type at compile time with a dynamic type

I am using typenum in Rust to add compile-time dimension checking to some types I am working with. I would like to combine it with a dynamic type so that an expression with mismatched dimensions would fail at compile time if given two incompatible ty