def _member(agent, term, intention):
choicepoint = object()
for member in agentspeak.evaluate(term.args[1], intention.scope):
intention.stack.append(choicepoint)
if agentspeak.unify(term.args[0], member, intention.scope,
intention.stack):
yield
agentspeak.reroll(intention.scope, intention.stack, choicepoint)
def _findall(agent, term, intention):
pattern = agentspeak.evaluate(term.args[0], intention.scope)
query = agentspeak.runtime.TermQuery(term.args[1])
result = []
memo = {}
for _ in query.execute(agent, intention):
result.append(agentspeak.freeze(pattern, intention.scope, memo))
if agentspeak.unify(tuple(result), term.args[2], intention.scope,
intention.stack):
yield
def test_belief(self, term, intention):
term = agentspeak.evaluate(term, intention.scope)
if not isinstance(term, agentspeak.Literal):
raise AslError("expected belief literal, got: '%s'" % term)
query = TermQuery(term)
try:
next(query.execute(self, intention))
return True
except StopIteration:
return False
def remove_belief(self, term, intention):
term = agentspeak.evaluate(term, intention.scope)
try:
group = term.literal_group()
except AttributeError:
raise AslError("expected belief literal, got: '%s'" % term)
choicepoint = object()
relevant_beliefs = self.beliefs[group]
for belief in relevant_beliefs:
intention.stack.append(choicepoint)
if agentspeak.unify(term, belief, intention.scope,
intention.stack):
relevant_beliefs.remove(belief)
return True
agentspeak.reroll(intention.scope, intention.stack, choicepoint)
return False
def execute(self, agent, intention):
# Boolean constants.
term = agentspeak.evaluate(self.term, intention.scope)
if term is True:
yield
return
elif term is False:
return
try:
group = term.literal_group()
except AttributeError:
raise AslError(
"expected boolean or literal in query context, got: '%s'" %
term)
# Query on the belief base.
for belief in agent.beliefs[group]:
for _ in agentspeak.unify_annotated(term, belief, intention.scope,
intention.stack):
yield
choicepoint = object()
# Follow rules.
for rule in agent.rules[group]:
rule = copy.deepcopy(rule)
intention.stack.append(choicepoint)
if agentspeak.unify(term, rule.head, intention.scope,
intention.stack):
for _ in rule.query.execute(agent, intention):
yield
agentspeak.reroll(intention.scope, intention.stack, choicepoint)
