double x = 2*x
isBig x = x>=100
listify x y = [x,y]

myAbs x = if x>=0 then x else -x

word n = case n of
  1 -> "one"
  2 -> "two"
  3 -> "three"
  _ -> "??"

sign' n
  | n>0        = 1
  | n<0        = -1
  | otherwise  = 0

myAnd False _ = False
myAnd True a = a
myAnd' _ False = False
myAnd' a True = a