How to check whether a name is an alias or a reference in C++17?

Question

From cppref

Like a reference, a structured binding is an alias to an existing object. Unlike a reference, the type of a structured binding does not have to be a reference type.

For example:

int a[2] = { 1, 2 };
auto [x, y] = a;

x and y are aliases rather than references. My question:

How to implement a type check function like is_alias_v<decltype(x)>?

Answer 1

I do not believe that such a thing is possible.

Fortunately, there is never any need for it.

Use x as if it were a nice juicy int, regardless of its origins. Because, well, that's what it is!

Also don't forget that x and y here don't alias or reference the elements of a, but an "invisible" copy.