 Term.parseTerm
  reservedOps ["=", "=="]
  right <- Term.parseTerm
  return $ Atom $ Predicate "Identity" [left, right]

parseNIdentity = do
  left
parseIdentity = do
  left <- Term.parseTerm
  reservedOps ["=", "=="]
  right <- Term.parseTerm
  return $ Atom $ Predicate "Identity" [left, right]
parseIdentity = do
  left <- Term.parseTerm
  reservedOps ["=", "=="]
  right <- Term.parseTerm
  return $ Atom $ Predicate "Identity" [left, right]