[Haskell-cafe] Newbie question

Pieter Laeremans pieter at laeremans.org
Fri Dec 29 21:33:23 EST 2006


I'm reading the Haskell school of expression by Paul Hudok. Great book.

However I would like some feedback about a solution to an exercise

The problem is quite simple :

define f1 and f2 (using higher order functions ) such that

f1 (f2 (*) [1..4]) 5 => [5,10,15,20]

I have come up with the following solution :

f2 :: (a->b)->[a] -> [b]
f2 f xs = map f xs
f1 fs a = map (applyOp a) fs
applyOp  b f = f b

But I guess there must be some more elegant way. f2 isn't at all  
And the applyOp sounds silly.

Any comments or suggestions are welcome.



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