RE: RPG400-L Digest, Vol 4, Issue 199

["Larry Ducie" <Larry_Ducie@xxxxxxxxxxx>]

Hi Ron,

<snip>
?* is the transaction type code numeric?
     c                   evalr     pay_type_test = paytyp  
     c                   testn                   pay_type_test          99
     c                   if        *in99
     c                   eval      sctax# = %int(paytyp)       
     c                   else
     c                   eval      msgdata = 'Invalid Transaction Type Code'
</snip>

I'd suggest using a MONITOR group:

1) In circumstances where errors are infrequent, it may run faster than
constantly checking, followed by conditional processing (if statements).
2) You are coding for success, but still trapping errors. This looks neater
(IMHO):

     c                   monitor
     c                   eval      sctax# = %int(paytyp)

     ?* If the transaction type code is not numeric, display error...
     c                   on-error
     c                   eval      msgdata = 'Invalid Transaction Type Code'
     c                   endmon

Here you've eliminated the need for pay_type_test and you allow the eval to
simply run. If there's an error it will be trapped and your message will be
displayed.

The great thing about using monitor groups is that you can "group"
statements, and monitor the lot. You can also have a hierarchy of on-error
blocks, starting with specific error types and getting more generic as you
go.

Very similar to using a java try-catch block, and definitely better than
littering your code with checks followed by if statements.

Cheers

Larry Ducie