norm ExpA (CallE (LamE [] (ReturnE e)) [])         = do  m <- ReturnE <$> norm ExpA e
                                                         norm ExpA m
norm ExpA (CallE (LamE [] (ReturnE e)) [])         = do  m <- ReturnE <$> norm ExpA e
                                                         norm ExpA m
norm ExpA (CallE (LamE [] (ReturnE e)) [])         = do  m <- ReturnE <$> norm ExpA e
                                                         norm ExpA m