std::array<T,N>::swap

 

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std::array

Member types
Member functions
Element access array::at array::operator[]    array::front array::back array::data Operations array::fill array::swap	Iterators array::beginarray::cbegin array::endarray::cend array::rbeginarray::crbegin    array::rendarray::crend	Capacity array::empty array::size array::max_size
Non-member functions
operator==operator<=> (C++20) get(std::array) swap(std::array) to_array (C++20)	operator|=operator<operator>operator<=operator>= (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)
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void swap( array& other )noexcept(/* see below */);		(since C++11) (constexpr since C++20)

Exchanges the contents of the container with those of other. Does not cause iterators and references to associate with the other container.

Parameters

other

-

container to exchange the contents with

Return value

(none)

Exceptions

noexcept specification:   noexcept(noexcept(swap(std::declval<T&>(), std::declval<T&>()))) In the expression above, the identifier swap is looked up in the same manner as the one used by the C++17 std::is_nothrow_swappable trait.	(until C++17)
noexcept specification:   noexcept(std::is_nothrow_swappable_v<T>)	(since C++17)

For zero-sized arrays,

noexcept specification:  

noexcept

  

Complexity

Linear in size of the container.

Example

Run this code

#include <array>#include <iostream>   template<class Os, class V> Os& operator<<(Os& os, const V& v){ os <<'{';for(auto i : v) os <<' '<< i;return os <<" } ";}   int main(){std::array<int, 3> a1{1, 2, 3}, a2{4, 5, 6};   auto it1 = a1.begin();auto it2 = a2.begin();int& ref1 = a1[1];int& ref2 = a2[1];   std::cout<< a1 << a2 <<*it1 <<' '<<*it2 <<' '<< ref1 <<' '<< ref2 <<'\n'; a1.swap(a2);std::cout<< a1 << a2 <<*it1 <<' '<<*it2 <<' '<< ref1 <<' '<< ref2 <<'\n';   // Note that after swap iterators and references stay associated with their original// array, e.g. `it1` still points to element a1[0], `ref1` still refers to a1[1].}

Output:

{ 1 2 3 } { 4 5 6 } 1 4 2 5 { 4 5 6 } { 1 2 3 } 4 1 5 2

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 2456	C++11	the noexcept specification is ill-formed	made to work

See also

std::swap(std::array) (C++11)

specializes the std::swap algorithm (function template)