hodiv.hs

{-# LANGUAGE FlexibleInstances #-}

lift2 op f g x = op (f x) (g x)

instance Num a => Num (a -> a) where
  (+) = lift2 (+)
  (*) = lift2 (*)
  abs = (.) abs
  signum = (.) signum
  negate = (.) negate
  fromInteger i _ = fromInteger i

instance Fractional a => Fractional (a -> a) where
  (/) = lift2 (/)
  fromRational r _ = fromRational r
{-
let t = sin / cos in map t [1,2,pi,4]
[1.557407724654902,-2.185039863261519,-1.2246467991473532e-16,1.1578212823495775]
-}