[Haskell-cafe] Re: instance Eq (a -> b)

Maciej Piechotka uzytkownik2 at gmail.com
Wed Apr 14 04:25:03 EDT 2010


On Wed, 2010-04-14 at 01:21 -0700, Ashley Yakeley wrote:
> Maciej Piechotka wrote:
> 
> > I guess that the fact that:
> > - It is costly.
> 
> No, it's not. Evaluating equality for "Bool -> Int" does not take 
> significantly longer than for its isomorph "(Int,Int)". The latter has 
> an Eq instance, so why doesn't the former?
> 

Hmm. Lazy semantics? Costs?

Except technical problems with checking it - is every stable sort
equivalent?

Also see second argument.

Regards
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