basic_syncbuf& operator=(basic_syncbuf&& rhs);

Effects: Calls emit() then move assigns from rhs.

After the move assignment *this has the observable state it would have had if it had been move constructed from rhs ([syncstream.syncbuf.cons]).

Postconditions:

• rhs.get_wrapped() == nullptr is true.
• this->get_allocator() == rhs.get_allocator() is true when allocator_traits<Allocator>::propagate_on_container_move_assignment::value is true; otherwise, the allocator is unchanged.

Remarks: This assignment operator disassociates rhs from its wrapped stream buffer, ensuring destruction of rhs produces no output.

void swap(basic_syncbuf& other);

Preconditions: Either allocator_traits<Allocator>​::​propagate_on_container_swap​::​value is true or this->get_allocator() == other.get_allocator() is true.

Effects: Exchanges the state of *this and other.