std::common_reference

Since C++20

Header: <type_traits>

Determines the common reference type of the types T…, that is, the type to which all the types in T… can be converted or bound. If such a type exists (as determined according to the rules below), the member type names that type. Otherwise, there is no member type. The behavior is undefined if any of the types in T… is an incomplete type other than (possibly cv-qualified) void.

# Declarations

template< class... T >
struct common_reference;

(since C++20)

# Notes

Feature-test macro Value Std Feature __cpp_lib_common_reference 202302L (C++23) Make std::common_reference_t of std::reference_wrapper a reference type

# See also