On Wed, 8 Jul 2009, Steve wrote:

On Wed, 2009-07-08 at 10:00 +0200, Henning Thielemann wrote:

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On Tue, 7 Jul 2009, roconnor@theorem.ca wrote:

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As much as I'd love gcd 0 0 to be 0, the major problem is that this change would contradict the Haskell 98 report.

There was a long thread about this issue some years ago that came to the conclusion that the current behaviour of gcd is algebraically most sound.

I don't believe there was any such conclusion. But if you can provide a link to the thread it would be interesting to see it.

There was a long thread about the issue in 2001 that came to the conclusion that "there is a lot of support for gcd 0 0 = 0" and "The strong default for H98 is "no change"". http://www.mail-archive.com/haskell@haskell.org/msg09883.html

You are right, I mixed that up. The mail you mention summarizes the thread with the name "gcd 0 0 = 0" http://www.haskell.org/pipermail/haskell/2001-December/008609.html