pTAL Reference Manual (H06.03+)

Procedures, Subprocedures, and Procedure
Pointers
HP pTAL Reference Manual—523746-005
14-26
Procedure Pointers
Procedure Pointers
Procedure pointers allow a program to call a variable dynamically or to call an
EXTENSIBLE procedure.
The syntax of procedure pointers is similar to the syntax of forward procedures;
however, instead of the keyword PROC, you declare a procedure pointer using the
keyword PROCPTR. As with a forward procedure, a procedure pointer fully specifies
the procedure’s attributes and formal parameters but has no body—a procedure
pointer does not include executable statements.
You can declare procedure pointers as:
•
Variables
•
Formal parameters
•
Structure fields
return-type
specifies that the procedure is a function that returns a result and indicates the
data type of the returned result, and can be any of:
•
BADDR
•
CBADDR
•
CWADDR
•
EXTADDR
•
FIXED
•
FIXED [(scale )]
•
INT
•
REAL
•
REAL(64)
•
PROCADDR
•
SGWADDR
•
SGBADDR
•
SGXWADDR
•
SGXBADDR
•
STRING
return-type
PROCPTR
procptr-name
formal-param-spec
formal-param-names
attributes ;
END
PROCPTR
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