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From: Stephen Leake <Stephen.Leake@gsfc.nasa.gov>
Subject: Re: access to controlled types
Date: 1999/02/04
Message-ID: <u679i3vzc.fsf@gsfc.nasa.gov>#1/1
X-Deja-AN: 440665031
References: <918079635.219550@outpost1.roc.accglobal.net>
Organization: NASA Goddard Space Flight Center -- Greenbelt, Maryland USA
Newsgroups: comp.lang.ada
Date: 1999-02-04T00:00:00+00:00
List-Id: <comp.lang.ada>

"Terry J. Westley" <twestley@buffalo.veridian.com> writes:

> In a new version of TASH, I've implmented an interface
> to Tcl objects (which are reference counted) with Ada
> controlled types.  I've been very impressed with how
> well this works in GNAT.
> 
> But, there are certain calls in the interface which
> return an access to a class-wide type.  It's easy to
> reference count these newly created objects, but since
> the access type is not controlled, the reference counts
> don't get decremented.  What's the solution?  Should I
> declare another controlled type which *contains* an
> access to the original controlled type?  Or, is there
> a better solution?

Perhaps the functions that return a class-wide access type should
simply be removed. Do they serve a real purpose in the system? Is
there another (safer) way to satisfy that need? I guess the latter is
what you are suggesting. But often, a function that violates an
abstraction truly does not belong.

-- Stephe