Correcting Towers of Hanoi Haskell Solution

I've been really having fun playing with Haskell. I found a solution via Wikipedia for the Towers of Hanoi. The solution is here http://www.kernelthread.com/projects/hanoi//html/hs.html.



This solution will not compile with ghci v6.12.1. This is the corrected solution I tested and confirmed works with ghci v6.12.1:



dohanoi :: (Num a) => a -> a -> a -> a -> [(a,a)]

dohanoi 0 _ _ _ = []

dohanoi n from to using = let m=n-1

in dohanoi m from using to ++ [(from,to)] ++ dohanoi m using to from



hanoi :: (Num a) => a -> [(a,a)]

hanoi n = dohanoi n 1 3 2