std::experimental::ranges::Semiregular
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Defined in header
<experimental/ranges/concepts>
template< class T >
concept bool Semiregular = Copyable<T> && DefaultConstructible<T>;
(ranges TS)
concept bool Semiregular = Copyable<T> && DefaultConstructible<T>;
The Semiregular concept specifies that a type is both copyable and default constructible. It is satisfied by types that behave similarly to built-in types like int, except that they need not support comparison with ==.