Case Expressions

With case we can also pattern match on the value after some computations when there is no need to bind the intermediate result.

  1. plus :: (Integer, Integer) -> Integer
  2. plus (x, y) = x + y
  4. sumUpTo :: Integer -> (Integer, Integer) -> Boolean
  5. sumUpTo x p = case plus p of
  6.                 10 -> true
  7.                 _ -> false
  8. > sumUpTo 1 (2,3)
  9. false
  11. > sumUpTo 1 (2,8)
  12. true