Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!munnari.oz.au!bruce!trlluna!ait!greg
From: greg@ait.trl.oz (Greg Aumann)
Newsgroups: comp.lang.eiffel
Subject: Re: What happens when you're gone and forgotten?
Message-ID: <1200@trlluna.trl.oz>
Date: 20 Mar 90 05:41:00 GMT
References: <1586@xyzzy.UUCP>
Sender: root@trlluna.trl.oz
Lines: 24

From article <1586@xyzzy.UUCP>, by langley@yoyodyne.rtp.dg.com:
> 
> How do I write a class so that a routine will get called
> every time the object is forgotten?
> 
> I ask "how do you define a destructor?"  Is it the case that
> for some reason this sort of functionality isn't useful in Eiffel?

I would very much like to have this sort of facility available for an
application that I am writing.  The application is written in Eiffel
and C and uses X windows.  There are two reasons that I would like to
have a destructor function.  One is to free memory that was malloc'ed
in the C part of the application but is linked to an Eiffel object.
The second is to free X resources in the X server which are also
similarly linked to an Eiffel object.  What I would like to be able to
do is to write a destructor which simply frees the non-Eiffel resources
when the corresponging Eiffel object is destroyed.  I realise that
such a facility can be dangerous but I think it is better to have it
than to try and free stuff explicitly (which is why there is a GC in
the first place).
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