20 Strings library [strings]

20.3 String classes [string.classes]

20.3.2 Class template basic_string [basic.string]

20.3.2.6 Modifiers [string.modifiers]

20.3.2.6.8 basic_string::swap [string.swap]

void swap(basic_string& s)
  noexcept(allocator_traits<Allocator>::propagate_on_container_swap::value ||
           allocator_traits<Allocator>::is_always_equal::value);

Ensures: *this contains the same sequence of characters that was in s, s contains the same sequence of characters that was in *this.

Throws: Nothing.

Complexity: Constant time.