Simulating Local Variables in RPG Programs
One of RPG's greatest faults, in my opinion, is the lack of local variables in subroutines. You can treat a variable (or indicator) as local to a subroutine by saving the variable's value upon entry to the subroutine, and restoring it when exiting. The code in 3 illustrates this. (Three dots indicate source code that would be needed for a complete program.)
One of RPG's greatest faults, in my opinion, is the lack of local variables in subroutines. You can treat a variable (or indicator) as local to a subroutine by saving the variable's value upon entry to the subroutine, and restoring it when exiting. The code in Figure 3 illustrates this. (Three dots indicate source code that would be needed for a complete program.)
Advantages of this technique are fewer chances for a subroutine to undesirably change a variable or indicator; fewer variables needed by the program; and easier copies of blocks of source from one program to another.
Simulating Local Varibles in RPG Programs
Figure 3 Simulating Local Variables in RPG
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Ted Holt is IT manager of Manufacturing Systems Development for Day-Brite Capri Omega, a manufacturer of lighting fixtures in Tupelo, Mississippi. He has worked in the information processing industry since 1981 and is the author or co-author of seven books.
MC Press books written by Ted Holt available now on the MC Press Bookstore.
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