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std::has_unique_object_representations

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Defined in header <type_traits>
template< class T >
struct has_unique_object_representations;
 (since C++17)

std::has_unique_object_representations is a UnaryTypeTrait.

If T is trivially copyable and if any two objects of type T with the same value have the same object representation, provides the member constant value equal true. For any other type, value is false.

For the purpose of this trait, two arrays have the same value if their elements have the same values, two non-union classes have the same value if their direct subobjects have the same value, and two unions have the same value if they have the same active member and the value of that member is the same.

It is implementation-defined which scalar types satisfy this trait, but unsigned(until C++20) integer types that do not use padding bits are guaranteed to have unique object representations.

If