Move-assign a basic_random_access_file
from
another.
basic_random_access_file & operator=( basic_random_access_file && other);
This assignment operator moves a random-access file from one object to another.
The other basic_random_access_file
object from which the move will occur.
Following the move, the moved-from object is in the same state as if
constructed using the basic_random_access_file(const executor_type&)
constructor.