cpp/types/add reference

Creates an lvalue or rvalue reference type of.

@1@ If is a function type that has no cv- or ref- qualifier or an object type, provides a member typedef  which is. If is an rvalue reference to some type, then  is. Otherwise, is.

@2@ If is a function type that has no cv- or ref- qualifier or an object type, provides a member typedef  which is, otherwise  is.