< cpp‎ | concepts
Defined in header <concepts>
template <class T>
concept Regular = std::Semiregular<T> && std::EqualityComparable<T>;
(since C++20)

The Regular concept specifies that a type is regular, that is, it is copyable, default constructible, and equality comparable. It is satisfied by types that behave similarly to built-in types like int, and that are comparable with ==.