std::basic_ostream::basic_ostream
From cppreference.com
< cpp | io | basic ostream
| explicit basic_ostream( std::basic_streambuf<CharT, Traits>* sb ); |
(1) | |
| protected: basic_ostream( const basic_ostream& rhs ) = delete; |
(2) | (since C++11) |
| protected: basic_ostream( basic_ostream&& rhs ); |
(3) | (since C++11) |
1) Constructs the basic_ostream object, assigning initial values to the base class by calling basic_ios::init(sb).
2) The copy constructor is protected, and is deleted. Output streams are not copyable.
3) The move constructor uses basic_ios<CharT, Traits>::move(rhs) to move all basic_ios members, except for the rdbuf(), from rhs into *this. This move constructor is protected: it is called by the move constructors of movable output stream classes std::basic_ofstream and std::basic_ostringstream, which know how to correctly move the associated streambuffer.
Parameters
| sb | - | streambuffer to use as output sequence |
| rhs | - | basic_ostream to initialize from |
Example
Run this code
#include <sstream> #include <utility> #include <iostream> int main() { // ERROR: copy ctor is deleted // std::ostream myout(std::cout); // OK: shares buffer with cout std::ostream myout(std::cout.rdbuf()); // ERROR: move constructor is protected // std::ostream s2(std::move(std::ostringstream() << 7.1)); // OK: move ctor called through the derived class std::ostringstream s2(std::move(std::ostringstream() << 7.1)); myout << s2.str() << '\n'; }
Output:
7.1