The NULLIFY statement disassociates a pointer from its target. It takes the following form:
Rules and Behavior
The initial association status of a pointer is undefined. You can use NULLIFY to initialize an undefined pointer, giving it disassociated status. Then the pointer can be tested using the intrinsic function ASSOCIATED.
The following is an example of the NULLIFY statement:
REAL, TARGET :: TAR(0:50) REAL, POINTER :: PTR_A(:), PTR_B(:) PTR_A => TAR PTR_B => TAR ... NULLIFY(PTR_A)
After these statements are executed, PTR_A will have disassociated status, while PTR_B will continue to be associated with variable TAR.
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