is there type trait that show if one type might contain value of other type

Question

Is there some type trait that checks, if one integral type can hold value of other integral type without data loss?

For example int32_t might hold uint16_t, uint8_t, int32_t, int16_t and int8_t.

However int32_t can not hold uint32_t, nor uint64_t or int64_t.

Update

I made naive solution and I am posting it as answer. I know one can use std::is_same but I think this way is more expressive.

Answer 1

We can take advantage of the existing language rules here.

For list-initialization, narrowing conversions are ill-formed. We are trying to detect narrowing conversions. Hence, to the void_t!

template <class X, class Y, class = void>
struct can_hold : std::false_type { };

template <class X, class Y>
struct can_hold<X, Y,
    void_t<decltype(X{std::declval<Y>()})>>
: std::true_type { };