Implict parameters and monomorphism

C.Reinke C.Reinke@ukc.ac.uk
Thu, 03 May 2001 14:46:44 +0100


> But most importantly, this was a bad example.  There was a much better
> one posted on this mailing list a while ago.  Does anyone remember it?
> 
>     -- Lennart

Perhaps I should mention a useful application of this game, somewhat
unhelpfully named "Representative thingies" in my Haskell corner:

  http://www.cs.ukc.ac.uk/people/staff/cr3/toolbox/haskell/

Load the file R.hs in your favourite Hugs (Hugs mode), and you'll
see things like this (see comments in R.hs for more examples):

  Main> foldl (+) 0 [1..4] :: Int
  10
  Main> foldr (+) 0 [1..4] :: Int
  10
  Main> foldl (+) 0 [1..4]
  ((((0 + 1) + 2) + 3) + 4)
  Main> foldr (+) 0 [1..4]
  (1 + (2 + (3 + (4 + 0))))

Well, I found it useful (and fun; just a pity that you can't overload
(implicit) application in Haskell;-)..

Claus