Re: Multiple Conditions on a DOW loop

Neither changing the order nor inverting the logic will effect the
results...that's basic Boolean logic.

In addition, short circuit evaluation for AND's stops with the first
FALSE; while short circuit evaluation for OR's stops with the first
TRUE.

HTH,
Charles

On Fri, Jun 12, 2009 at 4:32 PM, Loyd Goodbar<loyd@xxxxxxxxxxxxxx> wrote:

Swap position of the conditions:
dow myvariable <> 'A' and myvariable <> '';

Perhaps RPG employs "short circuit" evaluation. In your condition below
myvar is <> '' is already true ('A' <> '') so does not need to compare to
'A'. This switch makes the more restrictive condition be evaluated first
(unless optimization is in effect).

Or invert the logic:

dow not (myvariable = '' or myvariable = 'A');

HTH,
Loyd

On Fri, Jun 12, 2009 at 3:13 PM, Bryce Martin <BMartin@xxxxxxxxxxxx> wrote:

Ok Group.  I have run into an interesting problem...

I have this loop structure...

dow myVariable <> '' and myVariable <> 'A';
 // I do some stuff
// At some point myVariable could be set to '' or A or another value
// at which point we want to run the loop again.

enddo;

But when myVariable = 'A' the loop runs anyway.

Can we not put multiple conditions on a DOW loop?  Is my brain not reading
my logic correctly today?

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