Docs4dev
Docs
cpp / latest / utility / tuple / tuple-like.html

tuple-like, pair-like

template< class T >
concept tuple-like = /* see below */;
 (1) (since C++23)
(exposition only*)		 
template< class T >
concept pair-like =
    tuple-like<T> && std::tuple_size_v<std::remove_cvref_t<T>> == 2;
 (2) (since C++23)
(exposition only*)
1) A type T models and satisfies the concept tuple-like if std::remove_cvref_t<T> is a specialization of
(since C++26)
2) pair-like objects are tuple-like objects with exactly 2 elements.

Notes

tuple-like types implement the tuple protocol, i.e., such types can be used with std::get, std::tuple_element and std::tuple_size.

Elements of tuple-like types can be bound with structured binding.

See also

tuple-like and pair-like are used in the following standard library components:

constructs a new tuple
(public member function)
assigns the contents of one tuple to another
(public member function)
(removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(C++20)
lexicographically compares the values in the tuple
(function template)
(C++23)
determines the common reference type of a tuple and a tuple-like type
(class template specialization)
(C++23)
determines the common type of a tuple and a tuple-like type
(class template specialization)
(C++11)
creates a tuple by concatenating any number of tuples
(function template)
(C++17)
calls a function with a tuple of arguments
(function template)
(C++17)
construct an object with a tuple of arguments
(function template)
constructs new pair
(public member function of std::pair<T1,T2>)
assigns the contents
(public member function of std::pair<T1,T2>)
(C++20)
converts the subrange to a pair-like type
(public member function of std::ranges::subrange<I,S,K>)
(C++20)
takes a view consisting of tuple-like values and a number N and produces a view of Nth element of each tuple
(class template) (range adaptor object)

© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/w/cpp/utility/tuple/tuple-like