module Main where

(.?.) :: Bool -> (a, a) -> a
(.?.) True  = fst
(.?.) False = snd

infixl 3 .?.

(>:<) :: a -> b -> (a, b)
(>:<) = (,)

main :: IO ()
main = do
  print $ 3 == 5      .?. "yes" >:< "no" -- "no"
  print $ 5 > 3       .?. "yes" >:< "no" -- "yes"
  print $ 3 - 3 == 0  .?. "yes" >:< "no" -- "yes"
  print $ null []     .?. "yes" >:< "no" -- "yes"
  print $ null [1]    .?. "yes" >:< "no" -- "no"