## 9.3.16 ASSOCIATED (POINTER [, TARGET])

Description: | Returns the association status of its pointer argument or indicates whether the pointer is associated with the target.
Class: | Inquiry function; Generic
Arguments: | POINTER | Must be a pointer (of any data type).
| TARGET (opt) | Must be a pointer or target.
| The pointer (in POINTER or TARGET) must not have an association status that is undefined.
Results: | The result is a scalar of type default logical. If only POINTER appears, the result is true if it is currently associated with a target; otherwise, the result is false. If TARGET also appears and is a target, the result is true if POINTER is currently associated with TARGET; otherwise, the result is false. If TARGET is a pointer, the result is true if both POINTER and TARGET are currently associated with the same target; otherwise, the result is false. (If either POINTER or TARGET is disassociated, the result is false.) The setting of compiler options specifying integer size can affect this function.

Examples

Consider the following:

       REAL, TARGET, DIMENSION (0:50) :: TAR
       REAL, POINTER, DIMENSION (:) :: PTR
       PTR => TAR
       PRINT *, ASSOCIATED (PTR, TAR)     ! Returns the value true

The subscript range for PTR is 0:50. Consider the following pointer assignment statements:

       (1) PTR => TAR (:)
       (2) PTR => TAR (0:50)
       (3) PTR => TAR (0:49)

For statements 1 and 2, ASSOCIATED (PTR, TAR) is true because TAR has not changed (the subscript range for PTR in both cases is 1:51, following the rules for deferred-shape arrays). For statement 3, ASSOCIATED (PTR, TAR) is false because the upper bound of TAR has changed.

Consider the following:

       REAL, POINTER, DIMENSION (:) :: PTR2, PTR3
       ALLOCATE (PTR2 (0:15))
       PTR3 => PTR2
       PRINT *, ASSOCIATED (PTR2, PTR3)    ! Returns the value true
       ...
       NULLIFY (PTR2)
       NULLIFY (PTR3)
       PRINT *, ASSOCIATED (PTR2, PTR3)    ! Returns the value false

Previous Page Next Page Table of Contents