Re: [Haskell-cafe] Re: (flawed?) benchmark : sort

On Mar 11, 2008, at 0:20 , Chaddaï Fouché wrote:

2008/3/11, David Menendez :

...

I think Adrian is just arguing that a == b should imply f a == f b, for all definable f, in which case it doesn't *matter* which of two equal elements you choose, because there's no semantic difference.

I completely agree that this propriety should be true for all Eq instance exported by a public module. I don't care if it is not the case in a isolated code, but libraries shouldn't break expected invariant (or at least be very cautious and warn the user). Even Eq Double respects this propriety as far as I know.

I wouldn't want to bet on that (Eq Double, that is). Floating point's just *evil*. -- brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery@kf8nh.com system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH