{-# LANGUAGE LinearTypes #-}
{-# LANGUAGE NoImplicitPrelude #-}

import Prelude.Linear

f :: Ur Int %1 -> (Int, Int)
f (Ur x) = (x, x + 42)

g :: (Int, Int) %1 -> Int
g xy = let !(x, y) = xy
           -- won't work: 
           -- (x, y) = xy
           -- (!x, !y) = xy
       in x + y

main :: IO ()
main = print $ g (f (Ur 69))