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From: gudeman@cs.arizona.edu (David Gudeman)
Newsgroups: comp.lang.misc
Subject: Re: REFs or aliases?
Message-ID: <27113@megaron.cs.arizona.edu>
Date: 2 Nov 90 19:39:39 GMT
Organization: U of Arizona CS Dept, Tucson
Lines: 19

In article  <1990Nov1.204843.18771@newcastle.ac.uk> Chris.Holt@newcastle.ac.uk (Chris Holt) writes:
]
]Given an arbitrary domain, e.g. sets of integers, it is always
]possible to introduce a monadic operation f that extends that
]domain...
]
]The question is, why bother?...

That question can't be answered in the general form you presented,
because the answer depends on the specific domain and the specific
function that is being introduced.  E.g.: Why bother introducing
the negation operator into the set of counting numbers?  Answer, it
gives you solutions to equations of the form "a + i = 0" where "a > 0"
is some constant and "i" is a variable.
-- 
					David Gudeman
Department of Computer Science
The University of Arizona        gudeman@cs.arizona.edu
Tucson, AZ 85721                 noao!arizona!gudeman