shouldSucceedWith :: (Eq v, Show v, Show e) => Either e v -> v -> Expectation
(Left err)    `shouldSucceedWith` _         = expectationFailure . show $ err
shouldSucceedWith :: (Eq v, Show v, Show e) => Either e v -> v -> Expectation
(Left err)    `shouldSucceedWith` _         = expectationFailure . show $ err
(Left err)    `shouldSucceedWith` _         = expectationFailure . show $ err