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From: 880716a@aucs.uucp (Dave Astels)
Newsgroups: comp.lang.c++
Subject: destructors with MI
Message-ID: <1990Jun6.133126.4526@aucs.uucp>
Date: 6 Jun 90 13:31:26 GMT
Organization: Acadia University - School of Computer Science
Lines: 46


I have a class dag as follows:

class ConsCell {
	ConsCell *next;
// ...
}

class List {
	ConsCell * head, *tail;
public:
	~List ()  ...
// ...
}

class String {
	~String () ...
// ...
}

class ListCell : public ConsCell, public List {
// ...
}

class StringCell : public ConsCell, public String {
// ...
}

A List consists of a linked list of ConCells, pointed to by List::head,
List::tail is simple for makeing appending (a very much used operation)
more effient.  The ConsCells in this list are either ListCells or
StringCells.  Everything works fine except for destructing.

When a ListCell or StringCell gets destructed I want the List/String
destructor to be called.  ListCells & StringCells (and any future kinds
of Cells) are deleted from the List object containing them, thus they
are seen as ConsCells.

My question is: how do I get them to destruct as Lists/Strings when
they are deleted as ConsCells  ????

-- 
- Dave Astels

Internet: 880716a@AcadiaU.CA
Bitnet:   880716a@Acadia