On Mar 11, 2008, at 0:20 , Chaddaï Fouché wrote:
2008/3/11, David Menendez <[EMAIL PROTECTED]>:
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] [EMAIL PROTECTED]
system administrator [openafs,heimdal,too many hats] [EMAIL PROTECTED]
electrical and computer engineering, carnegie mellon university KF8NH
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