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From: gjc@batserver.cs.uq.oz (Cumming)
Newsgroups: comp.lang.eiffel
Subject: Operations on void references
Message-ID: <1470@moondance.cs.uq.oz>
Date: 8 Sep 89 10:11:19 GMT
Sender: news@moondance.cs.uq.oz
Reply-To: gjc@batserver.cs.uq.oz
Organization: Computer Science Department, The University of Queensland, Brisbane, Australia
Lines: 15

I am interested in knowing why routines may not operate on void references. An
obvious example is the traversal of a null tree.

Whereas I would like to write

	tree.traverse

I must actually write

	if not tree.void then
		tree.traverse

This seems unnecessary and very inconvenient in certain circumstances.

G.J. Cumming