Re: On Eq, was Re: [Haskell-cafe] When to use fancy types [Re: NumberTheory library]

G'day all. Quoting Jacques Carette :

From what you argue above, and reading the IEEE 754 standard correctly, instance Eq Float and instance Eq Double should be *removed* !

You could also argue that a function which distinguishes between +0 and -0 doesn't respect "semantic equality" of Float and Double. Your task, should you choose to accept it, is to define what the semantics of equality actually are for IEEE 754 floats. :-) Cheers, Andrew Bromage