testsuite/tests/typecheck/should_fail/TyAppPat_ExistentialEscape.hs


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{-# LANGUAGE TypeApplications #-}
{-# LANGUAGE GADTs #-}
{-# LANGUAGE ExistentialQuantification #-}
{-# LANGUAGE ScopedTypeVariables #-}

module Main where

data Some = forall a. Some a

foo (Some @a x) = (x :: a)

main = do
  print (foo (Some (5 :: Integer)) :: Integer)