testsuite/tests/deriving/should_fail/T1496.stderr


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T1496.hs:10:32:
    Could not coerce from ‛c Int’ to ‛c Moo’
      because ‛c Int’ and ‛c Moo’ are different types.
      arising from the coercion of the method ‛isInt’ from type
                   ‛forall (c :: * -> *). c Int -> c Int’ to type
                   ‛forall (c :: * -> *). c Int -> c Moo’
    Possible fix:
      use a standalone 'deriving instance' declaration,
        so you can specify the instance context yourself
    When deriving the instance for (IsInt Moo)