--fileName: ex1.hs

module ex1 where

import Prelude hiding (gcd)

gcd :: Int -> (Int -> Int)
gcd x y
   --if y=0 then the gcd is the value of x
   | y ==0 = x
   --if x=0 then the gcd is y
   | x ==0 = y
   --Apply the Euc. Alg recursively using (2*smaller#) and (larger#-2*smaller#)
   | x > y = gcd (2*y) (x-(2*y))
   --Otherwise y>= x
   |otherwise = gcd (2*x) (y-(2*x))

{-
I typed ':r' in ghci and got the following compiler error:

*Main> :r

ex1.hs:1:8: error: parse error on input `ex1'
  |
1 | module ex1 where
  |        ^^^
Failed, one module loaded.

<interactive>:1:1: error:
    Could not find module `Main'
    Use -v to see a list of the files searched for.
-}