# -*- coding: utf-8 -*-
# pytableaux, a multi-logic proof generator.
# Copyright (C) 2014-2023 Doug Owings.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
from __future__ import annotations
from . import LogicType
from . import fde as FDE
from . import tfde as TFDE
from . import kfde as KFDE
from . import s4 as S4
from . import t as T
from ..tools import group
class Meta(KFDE.Meta):
name = 'S4FDE'
title = 'FDE with S4 modal'
description = 'Modal version of FDE based on S4 normal modal logic'
category_order = 4
extension_of = ('TFDE')
class Model(TFDE.Model):
_ensure_reflexive_transitive = S4.Model._ensure_reflexive_transitive
def finish(self):
self._check_not_finished()
self._ensure_reflexive_transitive()
return super().finish()
class System(FDE.System): pass
[docs]
class Rules(LogicType.Rules):
closure = KFDE.Rules.closure
groups = (
# non-branching rules
KFDE.Rules.groups[0],
group(S4.Rules.Transitive),
# modal operator rules
*KFDE.Rules.groups[2:4],
group(T.Rules.Reflexive),
# branching rules & quantifier rules
*FDE.Rules.groups[-3:])
@classmethod
def _check_groups(cls):
for branching, i in zip(range(2), (0, -3)):
for rulecls in cls.groups[i]:
assert rulecls.branching == branching, f'{rulecls}'