std::Relation

 

C++

Language

Standard Library Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Concepts library

Core language concepts
Same DerivedFrom ConvertibleTo CommonReference Common	Integral SignedIntegral UnsignedIntegral Assignable SwappableSwappableWith	Destructible Constructible DefaultConstructible MoveConstructible CopyConstructible
Comparison concepts
Boolean	EqualityComparableEqualityComparableWith	StrictTotallyOrderedStrictTotallyOrderedWith
Object concepts
Movable Copyable	Semiregular Regular
Callable concepts
InvocableRegularInvocable	Predicate	Relation StrictWeakOrder

 

Defined in header <concepts>
template <class R, class T, class U> concept Relation =   std::Predicate<R, T, T> && std::Predicate<R, U, U> &&   std::Predicate<R, T, U> && std::Predicate<R, U, T>;	(1)	(since C++20)

The concept Relation<R, T, U> specifies that R defines a binary relation over the set of expressions whose type and value category are those encoded by either T or U.