Re: Unchecked_Conversion and task pointer.

"Dmitry A. Kazakov" <mailbox@xxxxxxxxxxxxxxxxx> wrote in message
news:tb8600lfqd2z.1l9etgzsgcls2.dlg@xxxxxxxxxxxxx
....
> > You can declare a task interface in Ada 200Y:
> >
> > type T_Int is task interface;
> >
> > I probably should have done that in my example.
>
> Can a task interface have entries?

No, there are no stand-alone entries. But a procedure can match an entry and
be called as an entry.

> > You are allowed to use the primitive procedures of an interface in a
timed
> > entry call, and they will work as an entry in that case.
>
> Does it mean that in Ada 200Y any procedure of an interface can be used as
> if it were an entry?

Any primitive procedure of an interface, yes. If it is not an entry, it is
treated as if it is immediately open.

....
> > I wasn't (and am still not) convinced that this is the right design, but
it
> > certainly works and has the needed effects. I think there will be some
> > confusion from a readability standpoint, but otherwise you can do
everything
> > with such a procedure that you can do with an entry (other than requeue
it;
> > no one can figure out how a dispatching requeue could work - it couldn't
> > have been allowed if dispatching entries existed, either).
>
> Why? Ignoring misleading prefix notation can be ignored, to have a
> dispatching requeue, the target task or protected object of the entry must
> be class-wide:

Well, you can't ignore the prefix (it determines whether it is an internal
or external requeue). And I believe that there was another problem as well.
(I don't remember what it was, sorry.) It certainly doesn't work with the
"use a procedure like an entry" model, because it would make no sense to
requeue on a procedure.

Randy.



.

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