If everyone likes this I'll put it in; otherwise I'll simply state that gcd 0 0 is defined to be 0. Christoph does not like this, but the weight of world opinion seems to be fairly clearly in favour of gcd 0 0 = 0. Let's try to wrap this one up. Simon | -----Original Message----- | From: Alan Bawden [mailto:Alan@LCS.MIT.EDU] | Sent: 17 December 2001 18:45 | To: haskell@haskell.org; Simon Peyton-Jones | Subject: Re: gcd 0 0 = 0 | | | From: Lars Henrik Mathiesen <thorinn@diku.dk> | Date: 17 Dec 2001 14:50:21 -0000 | ... | In case it isn't clear already, these definitions make a lattice on | the positive integers, with divides ~ leq, gcd ~ meet and | lcm ~ join, | using the report's definitions of gcd and lcm. | | Indeed, that's a nice way of putting it. How about if the report just | says: | | In order to make the non-negative integers into a lattice | under `gcd' | and `lcm', we define `gcd 0 0 = 0'. |