def is_literal_identified(self, literal: Literal):
"""
Is the given simple literal identified yet?
:param literal: the literal's data.
:return: the identification status.
"""
return literal.as_tuple() in self.identified_literals
def get_literal_number(self, literal: Literal):
"""
Get the number of an already-identified simple literal.
:param literal: the literal's data.
:return: the literal's identifier.
"""
return self.identified_literals[literal.as_tuple()]
def register_literal(self, literal: Literal) -> int:
"""
Add a new association for a given simple literal.
:param literal: the literal's data.
:return: the new identification number for the literal.
"""
old_number = self._current_number
self.identified_literals[literal.as_tuple()] = self._current_number
self.reverse_identified_literals[self._current_number] = literal
self._current_number += 1
return old_number