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Diffstat (limited to 'testsuite/tests/typecheck/should_fail/T20356.hs')
| -rw-r--r-- | testsuite/tests/typecheck/should_fail/T20356.hs | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/testsuite/tests/typecheck/should_fail/T20356.hs b/testsuite/tests/typecheck/should_fail/T20356.hs new file mode 100644 index 0000000000..6a847cb22a --- /dev/null +++ b/testsuite/tests/typecheck/should_fail/T20356.hs @@ -0,0 +1,18 @@ +{-# LANGUAGE TypeFamilies, PolyKinds, ConstraintKinds #-} + +module T20356 where + +import GHC.Types + +type family Id (a :: k -> Constraint) :: l -> Constraint +type instance Id f = f + +type T :: Constraint -> Constraint +type T = Id Eq + +data Proxy p = MkProxy + +id' :: f a -> f a +id' x = x + +z = id' (MkProxy @T) |