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):
if self.consequent:
accum = None
if self.conds:
accum = reduce(AndExpression, [c.fol() for c in self.conds])
if accum:
accum = ImpExpression(accum, self.consequent.fol())
else:
accum = self.consequent.fol()
for ref in self.refs[::-1]:
accum = AllExpression(ref, accum)
return accum
else:
if not self.conds:
raise Exception("Cannot convert DRS with no conditions to FOL.")
accum = reduce(AndExpression, [c.fol() for c in self.conds])
for ref in map(Variable, self._order_ref_strings(self.refs)[::-1]):
accum = ExistsExpression(ref, accum)
return accum
def fol(self):
e = AndExpression(self.first.fol(), self.second.fol())
if self.consequent:
e = ImpExpression(e, self.consequent.fol())
return e
