27 Feb
2006
27 Feb
'06
8:23 p.m.
On Mon, Feb 27, 2006 at 05:09:30PM +0300, Bulat Ziganshin wrote:
i had plans to propose the same and even more:
instance C2 a b | a/=b
I was thinking it would be all kinds of useful if we had two predefined classes class Eq a b class NEq a b where Eq has instances exactly when its two types are equal and NEq has instances exactly when its two types are not equal. Eq should be straightforward to implement, declaring any type automatically creates its instances. (sort of an auto-deriving). NEq might be more problematic as that would involve a quadratic number of instances so its implementation might need to be more special. but perhaps we can do with just 'Eq'. John -- John Meacham - ⑆repetae.net⑆john⑈