std::basic_istream<CharT,Traits>::swap
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basic_istream::swap
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protected:
void swap( basic_istream& rhs );
(since C++11)
void swap( basic_istream& rhs );
Calls basic_ios::swap(rhs) to swap all data members of the base class except for rdbuf(), and swaps the values of the gcount() counters between *this and rhs. This swap function is protected: it is called by the swap functions of the swappable input stream classes std::basic_ifstream and std::basic_istringstream , which know how to correctly swap the associated streambuffers.
[edit] Parameters
rhs
-
different
basic_istream object of the same type to swap with
[edit] Example
Run this code
#include <iostream> #include <sstream> #include <utility> int main() { std::istringstream s1("hello"); std::istringstream s2("bye"); s1.swap(s2); // OK, istringstream has a public swap() std::swap (s1, s2); // OK, calls s1.swap(s2) // std::cin.swap(s2); // ERROR: swap is a protected member std::cout << s1.rdbuf() << '\n'; }
Output:
hello