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std::array::swap(3)	       C++ Standard Libary	     std::array::swap(3)

NAME
     std::array::swap - std::array::swap

Synopsis
	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&>())))
									       (un-
     til C++17)
	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.
	noexcept						  specification:
     (since C++17)
	noexcept(std::is_nothrow_swappable_v<T>)

	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	retroac-
     tively to
	previously published C++ standards.

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

See also
	std::swap(std::array) specializes the std::swap algorithm
	(C++11) 	      (function template)

Categories:
	  * conditionally noexcept
	  * unconditionally noexcept

http://cppreference.com 	   2024.06.10		     std::array::swap(3)
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