std::basic_ostream::swap
From cppreference.com
< cpp | io | basic ostream
| protected: void swap(basic_ostream& rhs); |
(since C++11) | |
Calls basic_ios::swap(rhs) to swap all data members of the base class, except for rdbuf(), between *this and rhs. This swap function is protected: it is called by the swap functions of the swappable output stream classes std::basic_ofstream and std::basic_ostringstream, which know how to correctly swap the associated streambuffers.
Parameters
| rhs | - | a basic_ostream of the same type to swap with |
Example
Run this code
#include <sstream> #include <iostream> #include <utility> int main() { std::ostringstream s1("hello"); std::ostringstream s2("bye"); s1.swap(s2); // OK, ostringstream has a public swap() std::swap(s1, s2); // OK, calls s1.swap(s2) // std::cout.swap(s2); // ERROR: swap is a protected member std::cout << s1.str() << '\n'; }
Output:
hello