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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Ada Interfaces and the Liskov Substitution Principle
Date: Thu, 24 May 2007 17:44:42 -0500
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Date: 2007-05-24T17:44:42-05:00
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message
news:tii7nk5e3998$.1xfer2lqmixvy.dlg@40tude.net...
> On Thu, 24 May 2007 20:27:25 +0200, Pascal Obry wrote:
>
> > Randy Brukardt a �crit :
> >> Right. The most general type of interface is a limited interface; every
> >> interface should be declared limited if possible. (We didn't make that
the
> >> default solely because it would be inconsistent with the rest of the
> >> language.)
> >
> > Well a task type is limited by default, idem for a protected object
types.
>
> Randy probably meant that If it were limited then one would need to
> introduce "not limited" qualifier to be able to declare a non-limited
> interface. (In addition to awful "not null")

Correct, that's what I meant. When Ada has a choice between non-limited and
limited, it makes you write "limited" if you meant that. That's annoying in
this case, but it's less annoying than having:

    type A is tagged record...
    type B is tagged limited record ...
    type C is tagged private;
    type D is tagged limited private;
    type E is not limited interface;
    type F is interface;

which would be forever confusing.

                          Randy.