Re: Bug or Feature or missing PTF? Parameter passed by constant reference gets cleared!

[Charles Wilt <charles.wilt@xxxxxxxxx>]

Working as designed...

You're passing the same memory address twice.  So in effect, your procedure
is looking at the same place in memory via two "names".  So it makes sense
that the "input" name is cleared.

You could try to force the compiler to create a temporary copy for the
input value...but you'd run the risk that what works today won't work later.

Better would be to use VALUE instead of CONST

However, I personally think it'd be disconcerting to see
myproc(myvar:myvar);

Why not just use a single in/out parm?
myproc(myvar);

or even better IMO, as i make it clear there's a transformation going on.
myvar = myproc(myvar);

Charles


On Thu, Jun 13, 2013 at 12:44 PM, Birgitta Hauser <Hauser@xxxxxxxxxxxxxxx>wrote:

> Hi,
>
> I just run in the following situation:
> I call a procedure that expects an input parameter and an output parameter.
> (The output value is only the revised input value).
> The first parameter is passed by constant reference.
> In the caller I specify the same variable for Input and Output parameter.
>
> First thing that is done in the called procedure is, the output parameter
> is
> cleard.
> I expected the content of the input parameter (even though the same
> variable/address was passed) stays untouched.
> ... but after the clear both input and output parameters are empty!
>
> I'm currently working on an 7.1 system.
>
> Mit freundlichen Grüßen / Best regards
>
> Birgitta Hauser
>
> "Shoot for the moon, even if you miss, you'll land among the stars." (Les
> Brown)
> "If you think education is expensive, try ignorance." (Derek Bok)
> "What is worse than training your staff and losing them? Not training them
> and keeping them!"
>
>
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