Re: Explanation

Jon,

What would be the benefit of your 'true' CONST over VALUE - performance
only?

I guess I can see your point, but (and here I'm, only talking about parms
where the parameter doesn't need to be transformed) except for the
discussed scenario where the called program doesn't specify CONST, there
are very few occasions where a CONST parameter can be changed by the called
procedure anyway. How often do you run into those scenarios?

Rory

On Sun, Jun 17, 2012 at 2:33 PM, Jon Paris <jon.paris@xxxxxxxxxxxxxx> wrote:

On 2012-06-17, at 1:00 PM, rpg400-l-request@xxxxxxxxxxxx wrote:

Jon, isn't this what "VALUE" means?

I have long advocated that RPG should have const-and-I-mean-it whereby

a copy is _always_ made. Then const would mean what most people already
think it means!

No. VALUE parameters are passed by value i.e. copy of the data is made on
the stack and accessed by the callee. So the callee does not receive a
pointer - they get the actual data.

CONST parameters are normal parms - i.e. a pointer is passed regardless of
the size of the parm.

What I'm talking about would result in a regular pointer being passed but
it would be to a copy of the data. This is what happens now when a CONST
parm requires to be transformed due to data type / size differences.


Jon Paris

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www.SystemiDeveloper.com