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From: trodgers@nmsu.edu (Thomas Rodgers)
Newsgroups: comp.lang.pascal
Subject: Re: HELP WITH TURBO PASCAL 5.5 OOP!!! Please!
Message-ID: <TRODGERS.90Oct16155949@dante.nmsu.edu>
Date: 16 Oct 90 21:59:49 GMT
References: <2994@yang.earlham.edu>
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Organization: NMSU Computer Science
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In-reply-to: jeffb@yang.earlham.edu's message of 14 Oct 90 22:32:12 GMT

The constructor is required because virtual methods do not know
precisely which instance of the method is to be called until the
constructor code initializes a virtual method table within the object,
there is a discussion of the VMT in the reference section of the OOP
guide.  Also only a constructor can be specified in dynamic allocation
of an object (I think) (ie. new(Some_Obj,Init(X,Y,BLAH)).

The same holds for the destructor, so that when you deallocate an
object, dispose(Some_Obj,Done) performs any cleanup the object needs
before it is disposed of.