tests: remove extra_files.py (#12223)
[ghc.git] / testsuite / tests / typecheck / should_fail / tcfail098.hs
1 {-# LANGUAGE UndecidableInstances #-}
2
3 module ShouldFail where
4
5 -- The constraint in the context of an instance declaration
6 -- is ambiguous, but we have UndecidableInstances on, so
7 -- it could conceivably be ok (we'd need OverlappingInstances
8 -- too in this case). So we allow it.
9 -- See Note [The ambiguity check for type signatures] in TcMType
10
11 class Bar a
12 instance Bar a => Bar Bool
13