NAME¶

std::basic_osyncstream::operator= - std::basic_osyncstream::operator=

Synopsis¶

basic_osyncstream& operator=( std::basic_osyncstream&& other ); (since C++20)

Move-assigns a synchronized output stream:

Move-assigns the wrapped std::basic_syncbuf from the corresponding member of other
(after this move-assignment, other.get_wrapped() returns a null pointer and
destruction of other produces no output; any pending buffered output will be
emitted) and move-assigns the base std::basic_ostream (this swaps all stream state
variables except for rdbuf between *this and other)

Parameters¶

other - another synchronized output stream to move from

Return value¶

*this

Example¶

// Run this code

#include <iomanip>
#include <iostream>
#include <sstream>
#include <syncstream>
#include <utility>

int main()
{
std::osyncstream out(std::cout);
out << "test\n";
std::ostringstream str_out;
std::osyncstream{str_out} = std::move(out); // Note that out is emitted here
std::cout << "str_out = " << std::quoted(str_out.view()) << '\n';
}

Output:¶

test
str_out = ""

Defect reports

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

DR Applied to Behavior as published Correct behavior
the move assignment operator was noexcept, but
LWG 3867 C++20 std::basic_syncbuf's move assignment operator removed noexcept
is not

See also¶

constructor constructs a basic_osyncstream object
(public member function)
destructor destroys the basic_osyncstream and emits its internal buffer
(public member function)
calls emit() on the underlying basic_syncbuf to transmit its internal
emit data to the final destination
(public member function)