pTAL Conversion Guide

Procedures, Subprocedures, and Procedure
Pointers
pTAL Conversion Guide—527302-002
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Referencing Parameters
Referencing Parameters
In TAL, your code might reference one parameter relative to another. In TAL, this works
because TAL allocates memory for parameters in the same order as they are declared
in your program.
In pTAL, you cannot make assumptions about the order in which parameters are
allocated in memory. You must refer to each parameter only as a named entity. Do not
use a parameter as a base off of which to reference other parameters.
Guidelines:
•
Do not treat a procedure’s formal parameters as an implied array or implied
structure.
•
Do not index a parameter to access another parameter or local variable.
•
Do not perform block moves in which the source or destination spans more than
one parameter.
•
Do not pass the address of a value parameter to another procedure that expects
the address of an array or structure.
•
Do not step through a parameter list using indexing and address calculations.