From: "Jeffrey R. Carter" <spam.jrcarter.not@acm.nospam.org>
Subject: Re: Another question about controlled types.
Date: Sat, 09 Feb 2008 21:50:02 GMT
Date: 2008-02-09T21:50:02+00:00 [thread overview]
Message-ID: <eeprj.23080$9j6.1361@attbi_s22> (raw)
In-Reply-To: <47ae13b2$0$32493$4d3efbfe@news.sover.net>
Peter C. Chapin wrote:
> I'm using GNAT GPL 2007. I understand that Ada 2005 allows one to return
> limited types from functions. Consider the following package
> specification and body:
>
> package Check is
> type Some_Type is limited private;
> function Make(I : Integer) return Some_Type;
> private
> type Some_Type is
> record
> Component : Integer;
> end record;
> end Check;
The full view is not limited.
> with Ada.Finalization;
>
> package Check is
> type Some_Type is limited private;
> function Make(I : Integer) return Some_Type;
> private
> type Some_Type is new Ada.Finalization.Limited_Controlled with
> record
> Component : Integer;
> end record;
> end Check;
Here the full view is limited. That is the difference.
To return a limited value, you now need to either return an aggregate or use the
extended return statement:
return Some_Type'(Ada.Finalization.Limited_Controlled with Component => I);
or
return Result : Some_Type do
Result.Component := I;
end return;
See ARM 6.5.
--
Jeff Carter
"I soiled my armor, I was so scared."
Monty Python & the Holy Grail
71
next prev parent reply other threads:[~2008-02-09 21:50 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-02-09 20:57 Another question about controlled types Peter C. Chapin
2008-02-09 21:50 ` Jeffrey R. Carter [this message]
2008-02-09 23:41 ` Peter C. Chapin
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