Re: Advantages of RPG

GKern@xxxxxxxxxxxxxxxx wrote:

Now a really cool thing is that if you don't reference a field in the program, and try to debug the program and try to display a non-referenced variable, even though it is in the record read, that variable isn't available to the debugger. That's because the compiler is smart enough to know that an unreferenced variable isn't used and therefore shouldn't waste memory. (How's that for preemptive garbage collection/prevention!)

That's true of the OPM RPG compiler, but not of the ILE RPG compiler. (Except starting in V6R1 it _can_ be true if you specify OPTION(*NOUNREF).

Before V6R1, and by default even in V6R1, unreferenced variables are generated into the program. You can evaluate them in the debugger, but their values will never change from blank/zero because the ILE RPG compiler does do the optimization where it doesn't load the unreferenced fields on an input operation. (That can be very confusing; I can't guess if it's more or less confusing than when the debugger says the variable doesn't exist.)