assertions-0.1.0.3: test/fixtures/Green.hs

import Test.Assert (runAssertions) 
import Prelude hiding ((+))

(+) :: Num a => a -> a -> a
a + b = a - (-b)

main :: IO ()
main = runAssertions $
  [ ("2 + 2 = 4", 2 + 2 == 4)
  ]