Procedure pointer assignment (Fortran 2003)
The procedure pointer assignment statement causes a procedure pointer to become associated with a target or causes the procedure pointer's association status to become disassociated or undefined.
- proc_target
- is an expression or a procedure name. If proc_target is
an expression, it must be a function that returns a procedure pointer.
If proc_target is a procedure name, it must
be the name of an external procedure, a module procedure, a dummy
procedure, an intrinsic procedure that can be passed as an actual
argument, or another procedure pointer.
proc_target can also be the name
of an internal procedure.
proc_target must
not be an elemental procedure. - proc_pointer_object
- is a procedure pointer.
If proc_target is not a procedure pointer, proc_pointer_object becomes associated with proc_target. If proc_target is a procedure pointer and is associated with a procedure, proc_pointer_object becomes associated with the same procedure. If proc_target is a pointer with an association status of disassociated or undefined, proc_pointer_object acquires the same status.
If the proc_pointer_object has an explicit interface, its characteristics must be the same as proc_target except that proc_target can be pure even if proc_pointer_object is not. If the characteristics of proc_pointer_object or proc_target are such that an explicit interface is required, both proc_pointer_object and proc_target must have an explicit interface.
If proc_pointer_object has an implicit interface and is explicitly typed or referenced as a function, proc_target must be a function. If proc_pointer_object has an implicit interface and is referenced as a subroutine, proc_target must be a subroutine.
If proc_target and proc_pointer_object are functions, they must have the same type; corresponding type parameters must either be both deferred or have the same value.
If proc_target is a specific procedure name that is also a generic name, only the specific procedure is associated with proc_pointer_object.
