Template:cpp/io/basic spanstream/operator=

@1@ Move assigns the to, effectively move-assigning both the std base class subobject and the wrapped std.

@2@ Copy assignment operator is deleted. is not copy assignable.

Note that move assignment operator of the base class swaps all stream state variables (except for ) between and.

It is implementation-defined whether the std wrapped in still holds an underlying buffer after the move assignment.