Path: utzoo!mnetor!uunet!husc6!cmcl2!rutgers!bellcore!faline!ulysses!sfmag!sfsup!grk
From: grk@sfsup.UUCP (G.R.Kuntz)
Newsgroups: comp.lang.c++
Subject: dynamic vs. static binding
Message-ID: <2658@sfsup.UUCP>
Date: 22 Jan 88 14:53:49 GMT
Organization: AT&T-IS, Summit N.J. USA
Lines: 55

I've recently been reading Brad Cox's book "Object Oriented Programming"
and some of the examples that he gives are causing me a dilemma.  Let's
say we have a dynamically bound OO language and we want to write the
following program (syntax is C++/SMALLTALK/kludge):

	class container {
		// ...
	public:
		message("add:");
		message("weight");
	};

	class pen {
		// ...
	public:
		message("weight");
	};

	class pencil {
		// ...
	public:
		message("weight");
	};

	class eraser {
		// ...
	public:
		message("weight");
	};

	container pencilBox;
	pen pen1, pen2, pen3;
	pencil pencil1, pencil2;
	eraser eraser1, eraser2, eraser3;

	pencilBox.add(pen1);
	pencilBox.add(pen2);
	pencilBox.add(pen3);
	pencilBox.add(pencil1);
	pencilBox.add(pencil2);
	pencilBox.add(eraser1);
	pencilBox.add(eraser2);
	pencilBox.add(eraser3);

	cout << pencilBox.weight();

My question:  is there any general way of writing the container class in
a statically bound language without writing a ``container_thingie''
class and having all objects that may potentially be put in a container
be derived from container_thingie?

P.S. cat flames > /dev/null
-- 
	G. Ralph Kuntz N2HBN	grk@attunix.att.com
				N2HBN @ KB1BD-4