cpp/utility/functional/move only function/operator()

Invokes the stored callable target with the parameters. The, , and parts of  are identical to those of the template parameter of.

Equivalent to, where is a cv-unqualified lvalue that denotes the target object of , and  is equivalent to:
 * if  is either empty or, or
 * if  is either  or, or
 * if  is, or
 * if  is.

The behavior is undefined if is empty.

Return value
.

Exceptions
Propagates the exception thrown by the underlying function call.