Re: functor

Wolfgang Jeltsch wrote (on 29-10-01 23:43 +0100):

you cannot use sections with types and (->). Furthermore the variable must begin with a lowercase letter. So you have to write instance Functor (->) a where.

Actually, you have to write: instance Functor ((->) a) where since class Functor has arity *. This works because (->) a = (a ->) The outer parentheses are only there to ensure that the expression gets parsed as one argument, and not two. -- Frank Atanassow, Information & Computing Sciences, Utrecht University Padualaan 14, PO Box 80.089, 3508 TB Utrecht, Netherlands Tel +31 (030) 253-3261 Fax +31 (030) 251-379