Re: Default expression only allowed for "in" parameters - why?

[Robert A Duff <bobduff@world.std.com>]

"Smark" <not.provided@all.com> writes:

> procedure Do_Something (Data   : in Some_Type;
>                         Status : out Status_Type := Ok);
> 
> It also seemed like a strange idea, because I never recalled seeing
> it done.  Sure enough, it is prohibited by the LRM.  What is the
> rationale for this?

If defaults were allowed for 'out' params, I would think it ought to
mean that this is the default variable to pass to the parameter, not a
default initial value for it.  In Ada, a default applies if the
parameter is not explicitly given at the call site.  Are you saying that
Status should be initialized to OK if the actual parameter is specified?

Defaults for 'out' params were allowed in Green.  I don't know why they
were removed.  Perhaps the fact the you and I disagree on what they
ought to mean is a hint.

- Bob