diff options
Diffstat (limited to 'testsuite/tests/typecheck/should_fail/tcfail108.hs')
| -rw-r--r-- | testsuite/tests/typecheck/should_fail/tcfail108.hs | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/testsuite/tests/typecheck/should_fail/tcfail108.hs b/testsuite/tests/typecheck/should_fail/tcfail108.hs new file mode 100644 index 0000000000..5ccebde83e --- /dev/null +++ b/testsuite/tests/typecheck/should_fail/tcfail108.hs @@ -0,0 +1,9 @@ +-- The instance decl is illegal without UndecidableInstances + +module ShouldFail where + +data Rec f = In (f (Rec f)) + +instance Eq (f (Rec f)) => Eq (Rec f) where + (In x) == (In y) = x == y + |