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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Breaking a circularity
Date: Mon, 28 Mar 2011 12:37:12 +0100
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Date: 2011-03-28T12:37:12+01:00
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Ludovic Brenta <ludovic@ludovic-brenta.org> writes:

> BTW, why does Event_Type have to be limited? If it weren't limited,
> you would not need Event_Ptr_Type.  Also, why does it have to be
> abstract?

When I made my events limited, it was because any two events are
different. In this case, we have

   type Event_Type is abstract record
      Id : Positive;
      Time : Time_Type;
   end record;

so it probably won't make any sense for an Event to be copyable (what
would Id be in the copy?). Of course the events could be privately
nonlimited.

I do wonder what Id is _for_.

You'll certainly need pointers somewhere, because Event_Type instances
have to be held in the Queue. Indefinite_Ordered_Sets might do the
trick, though. It would save the bother of having Handle deallocate the
Event.