def assumptions(self):
"""
- Domain = union([e.free()|e.constants() for e in all_expressions])
- if "d1 = d2" cannot be proven from the premises, then add "d1 != d2"
"""
assumptions = self._command.assumptions()
domain = list(get_domain(self._command.goal(), assumptions))
# build a dictionary of obvious equalities
eq_sets = SetHolder()
for a in assumptions:
if isinstance(a, EqualityExpression):
av = a.first.variable
bv = a.second.variable
# put 'a' and 'b' in the same set
eq_sets[av].add(bv)
new_assumptions = []
for i, a in enumerate(domain):
for b in domain[i + 1:]:
# if a and b are not already in the same equality set
if b not in eq_sets[a]:
newEqEx = EqualityExpression(VariableExpression(a),
VariableExpression(b))
if Prover9().prove(newEqEx, assumptions):
# we can prove that the names are the same entity.
# remember that they are equal so we don't re-check.
eq_sets[a].add(b)
else:
# we can't prove it, so assume unique names
new_assumptions.append(-newEqEx)
return assumptions + new_assumptions
def assumptions(self):
assumptions = self._command.assumptions()
predicates = self._make_predicate_dict(assumptions)
new_assumptions = []
for p in predicates:
predHolder = predicates[p]
new_sig = self._make_unique_signature(predHolder)
new_sig_exs = [VariableExpression(v) for v in new_sig]
disjuncts = []
# Turn the signatures into disjuncts
for sig in predHolder.signatures:
equality_exs = []
for v1, v2 in zip(new_sig_exs, sig):
equality_exs.append(EqualityExpression(v1, v2))
disjuncts.append(reduce(lambda x, y: x & y, equality_exs))
# Turn the properties into disjuncts
for prop in predHolder.properties:
# replace variables from the signature with new sig variables
bindings = {}
for v1, v2 in zip(new_sig_exs, prop[0]):
bindings[v2] = v1
disjuncts.append(prop[1].substitute_bindings(bindings))
# make the assumption
if disjuncts:
# disjuncts exist, so make an implication
antecedent = self._make_antecedent(p, new_sig)
consequent = reduce(lambda x, y: x | y, disjuncts)
accum = ImpExpression(antecedent, consequent)
else:
# nothing has property 'p'
accum = NegatedExpression(self._make_antecedent(p, new_sig))
# quantify the implication
for new_sig_var in new_sig[::-1]:
accum = AllExpression(new_sig_var, accum)
new_assumptions.append(accum)
return assumptions + new_assumptions
def fol(self):
return EqualityExpression(self.first.fol(), self.second.fol())
