RE: compile error on %lookup where array is the return value

It's not strange...
This is principle:
if you pass EXPRESSION to subprocedure sprocedure is receiving address of 
temporary memory location that stores expression result. theoreticly that 
part of memory is not allocated for your PGM so you can't directly change 
it.

By defining CONST in prototype you garant to caller that received value 
want be changed in subprocedure so system lets you receive that tmp 
address.
By defining VALUE in prototype system makes copy of result of expr and 
sends new address to subprocedure so you are allowed to do wat you want 
with received value.

Both approachs work if you want your subproc to accept the expressions. 
For more take a look at SourcersGuide at page 50/51 (Chapter3-Power of 
prototyping).

There is no written in documentation that %LOOKUP bif doesn't accept 
expresions in second parm but obviously it doesn't :)

Igor Bešlić, dipl. ing. rač. 
VOLKSBANK d.d.
OJ Informatika
Varšavska 9, 10000 Zagreb
tel: +385 1 4801 895



"Lim Hock-Chai" <Lim.Hock-Chai@xxxxxxxxxxxxxxx> 
Sent by: rpg400-l-bounces@xxxxxxxxxxxx
13.01.2006 22:59
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RE: compile error on %lookup where array is the return value






You are right, it compiled normally when const/value keyword is present.
Otherwise it failed.  That is strange.



-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx
[mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of Jon Paris
Sent: Friday, January 13, 2006 3:27 PM
To: rpg400-l@xxxxxxxxxxxx
Subject: RE: compile error on %lookup where array is the return value

 >> This works because myLookup always returns 1 AND there is no %lookup
with an expression in the array name parameter.

You forced me to look again Mel - it appears to work because of the
const keyword on the proto for MyLookup.

getArray is a function that returns an array and yet is acceptable as a
parm to MyLookup.  If you remove the const keyword it will not compile.