RE: Parameter prototype question

Rory,

After a program verifies without errors in WDSCi, I then double-click a warning to load the source with all the warnings, then go through it. Mainly I'm looking for unused variables to remove, though it's also nice seeing when a procedure has a return variable that isn't handled. Adding a situation where there is a mismatch on a Const parameter wouldn't be bad to see either. However I prefer to always be aware of the field definition and the parameter definition when coding.

-Kurt

-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx [mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of Rory Hewitt
Sent: Friday, May 14, 2010 11:14 PM
To: RPG programming on the IBM i / System i
Subject: Re: Parameter prototype question

Mark,

No-one ever looks at compiler warnings. If it compiles, it's good to go :)
Seriously, do you ever look at those severity 10 warnings? I guess it could
be a compiler option, but surely it would have to flag every instance where
a user tries to pass a big field (perhaps at runtime with a validly low
value) to a small parameter? If so, then there could just be so many of
them, it would be pointless - I would certainly ignore them.

Barbara,

You're right of course, but if the problem occurs when the compiler attempts
to copy the value to a temporary 5P 0 field, the error is less 'obvious'
isn't it? didn't the OP say something about not being able to see why the
procedure wasn't being called - he was stepping through and the procedure
"wasn't being called" or something like that? At least with an explicit
copy, the error is pretty obvious and easy to debug.

Mind you, I use CONST or VALUE and check my code up-front :)

Rory

On Fri, May 14, 2010 at 6:35 PM, Mark S. Waterbury <mark.s.waterbury@xxxxxxx

wrote:

Hi, Barbara:

Given this whole set of problematic scenarios, would it perhaps not be
an improvement to have perhaps a new option on the compile commands to
allow the RPG IV compiler to at least flag these situations with a
WARNING message? Then, at least the programmer could look at those
warnings and perhaps take preventive / corrective action accordingly.

Mark S. Waterbury

> On 5/14/2010 8:24 PM, Barbara Morris wrote:

Rory Hewitt wrote:

...
However, if you *don't* have CONST specified, you always have to move

the

value from the 10P 0 field into a 5P 0 work field to pass it to the
procedure. Since that process (before you've even called the procedure)

will

stop you from passing a value that's> 99999, then the procedure call

itself

will never fail. ...

It's true that the procedure call won't fail, but you've just shifted
the problem to the assignment statement where you set up your 5P

variable.

If the 10P variable has a value bigger than 99999, you will get an
exception no matter how you try to pass it to a 5P parameter. The
exception will happen either when you copy it to your own 5P variable to
satisfy the non-CONST parameter, or when the compiler copies it to its
5P temporary for the CONST parameter.

So you not only have to manually verify every CONST or VALUE parameter,
you also have to manually verify every assignment. Or, to put it
another way, if for some reason you don't need to manually verify every
assignment, you shouldn't need to verify CONST and VALUE parameters

either.

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