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

NAME
     std::basic_string::swap - std::basic_string::swap

Synopsis
	void  swap(  basic_string&  other  );				  (until
     C++17)
	void swap( basic_string& other )  noexcept(/*  see  below  */);   (since
     C++17)
								     (constexpr
     since C++20)

	Exchanges  the contents of the string with those of other. All iterators
     and
	references may be invalidated.

	The behavior is undefined if Allocator does not propagate  on  swap  and
     (since C++11)
	the allocators of *this and other are unequal.

Parameters
	other - string to exchange the contents with

Return value
	(none)

Complexity
	Constant.

Exceptions
	No		    exception		      is		 thrown.
     (until C++11)
	Exceptions can only be thrown in the case where the behavior is
	undefined (see above).
									       (since
     C++11)
	If an exception is thrown for any reason, this function has no effect
	(strong exception safety guarantee).

	noexcept specification:
	noexcept(std::allocator_traits<Allocator>::propagate_on_con-
     tainer_swap::value (since
	||
     C++17)
		 std::allocator_traits<Allocator>::is_always_equal::value)

Example
     // Run this code

      #include <iostream>
      #include <string>

      int main()
      {
	  std::string a = "AAA";
	  std::string b = "BBBB";

	  std::cout << "Before swap:\n"
		       "a = " << a << "\n"
		       "b = " << b << "\n\n";

	  a.swap(b);

	  std::cout << "After swap:\n"
		       "a = " << a << "\n"
		       "b = " << b << '\n';
      }

Output:
      Before swap:
      a = AAA
      b = BBBB

      After swap:
      a = BBBB
      b = AAA

	Defect reports

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

	  DR	 Applied  to	      Behavior as published		 Correct
     behavior
	LWG 403 C++98	   swap() might throw an exception	   no  exception
     is thrown
	LWG  535  C++98       swapping strings did not preserve the   orders are
     also preserved
			   character orders

See also
	swap	    swaps the values of two objects
		    (function template)
	swap_ranges swaps two ranges of elements
		    (function template)
	swap	    swaps the contents
		    (public	  member       function       of	std::ba-
     sic_string_view<CharT,Traits>)

Category:
	  * conditionally noexcept

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