Are indicators evil creatures or victims of poor shop standards?

[Buck Calabro <buck.calabro@xxxxxxxxxxxxxxxxx>]

Booth Martin wrote:

> I'm watching all of the bashing of COMP and of indicators.  These are good
> tools.  Old, understood, and true;  much like a hammer or a shovel.  The
> hammer and the shovel don't change much, a better shovel or a better
> hammer really hasn't been invented.  So sure, there's newer fads and
> fancier solutions, but indicators are not evil creatures for pete's sake.

Booth,
I would say that indicators aren't evil per se, but they do suffer from at
least two serious drawbacks:
1) They are cryptic (or terse, if you prefer)
2) They are global.

Some people find the terseness of indicators to be an asset rather than a
liability.  That's a personal preference, but by and large trsnss =
not(gdthng).  One can assign names to indicators (to alleviate the
terseness) using a construct like the one below, but traditional RPG
programmers find this... excessive.
      * Indicators are mapped to field names                 
     D@Indicators      S               *   Inz(%addr(*IN))   
     DIndicators       DS                  Based(@Indicators)
     D Exit                   03     03                      
     D AddRec                 09     09                      
     D Alarm                  30     30                      
     D SflClr                 40     40                      

The major drawback that indicators suffer from is the fact that they are
global in scope: an indicator can be changed by almost any line in an RPG
program - and also by lines in DDS too!  (Not only CF keys, but there's a
SETOFF as well...)  If terseness is not a good thing, global scope is
downright nasty.  Quick - what indicators are set here:  EXSR GETDATE?  What
fields are input or output from it?  How about this: EVAL
ARDATE=GETDATE("ARDATE")?

Global variables pretty much require strong shop standards; it is the lack
of shop standards that has resulted in messy code, and it is messy code
which has given indicators a bad name.  If you have strong shop standards,
please PLEASE post them for the common good!

Buck Calabro
Aptis; Albany, NY

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