[Haskell-beginners] Does this function already exist in one of the standard modules?

Felipe Lessa felipe.lessa at gmail.com
Sat Aug 8 16:38:23 EDT 2009


On Sat, Aug 08, 2009 at 03:01:34PM -0500, I. J. Kennedy wrote:
> Does this function already exist in one of the standard modules?
> It computes  f(f(f(...f(x))).  I suspect it is a common function, but I
> can't find it, even using Hoogle.
>
>   applyMany :: Int -> (a -> a) -> a -> a
>   applyMany 0 f x = x
>   applyMany n f x = applyMany (n-1) f (f x)

applyMany n f x = iterate f x !! n

--
Felipe.


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