lazy pattern match in Haskell

lazy_pattern_match.hs

import Data.Function (fix)

-- lazy pattern match example
(is_odd, is_even) =
  fix
    ( \ ~(is_odd, is_even) ->
        ( (\n -> if n == 0 then False else is_even (n - 1))
        , (\n -> if n == 0 then True else is_odd (n - 1))
        )
    )