diff options
Diffstat (limited to 'testsuite/tests/typecheck/should_fail/T20666a.hs')
| -rw-r--r-- | testsuite/tests/typecheck/should_fail/T20666a.hs | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/testsuite/tests/typecheck/should_fail/T20666a.hs b/testsuite/tests/typecheck/should_fail/T20666a.hs new file mode 100644 index 0000000000..b1e4d2c174 --- /dev/null +++ b/testsuite/tests/typecheck/should_fail/T20666a.hs @@ -0,0 +1,12 @@ +{-# LANGUAGE UndecidableInstances #-} +{-# LANGUAGE TypeFamilies #-} + +module T20666a where + +type family F a + +class Eq (F a) => D a +class Eq (F a) => C a + +instance D [a] => C [a] + |