def parse_domain(domain_strips_generator):# domain generator rename?
iterator = iter(domain_strips_generator)
if (iterator.next() != "define"):
raise Error("STRIPS domain file does not contain define")
domain_definition = iterator.next()
#Check for errors in the domain file
if (domain_definition[0] == "domain" and len(domain_definition) == 2):
yield domain_definition[1]
else:
raise Error("STRIPS domain file is not structured properly")
requirements = iterator.next()
if requirements[0] == ":requirements":
yield requirements[1] #contains :typing
types = iterator.next()
else:
types = requirements
the_types = [strip_types.Type("object")]
if types[0] == ":types":
the_types.extend(strip_types.parse_typed_list(types[1:],
constructor=strip_types.Type))
constants = iterator.next()
else:
constants = types
yield the_types
if constants[0] == ":constants":
yield strip_types.parse_typed_list(constants[1:])
pred = iterator.next()
else:
yield []
pred = constants
if (pred[0] != ":predicates"):
raise Error("STRIPS domain file does not contain predicates")
yield ([predicates.Predicate.parse(entry) for entry in pred[1:]]
+
[predicates.Predicate("=",
[strip_types.TypedObject("?x", "object"),
strip_types.TypedObject("?y", "object")])]) #Equality predicate; thanks to Walid
#Only actions left if it is a STRIPS file; read all the remaining entries in the generator
remaining_entries = [action for action in iterator]
the_actions = []
for act in remaining_entries:
action = actions.Action.parse(act)
the_actions.append(action)
yield the_actions
def parse(action_list):
iterator = iter(action_list)
if (iterator.next() != ":action"):
raise Error("STRIPS file does not contain actions")
name = iterator.next()
params = iterator.next()
if params == ":parameters":
parameters = strip_types.parse_typed_list(iterator.next())
precond = iterator.next()
else:
parameters = []
precond = params
if precond == ":precondition":
precondition = conditions.parse_condition(iterator.next())
effect_iter = iterator.next()
else:
precondition = conditions.Conjunction([])
effect_iter = precond
assert effect_iter == ":effect"
effect_list = iterator.next()
eff = []
cost = effects.parse_effects(effect_list, eff)
for rest in iterator:
assert False, rest
return Action(name, parameters, precondition, eff)
def parse_problem(problem_strips_generator):
iterator = iter(problem_strips_generator)
if (iterator.next() != "define"):
raise Error("STRIPS problem file does not contain define")
problem_definition = iterator.next()
#Check for errors in the problem file
if (problem_definition[0] == "problem" and len(problem_definition) == 2):
yield problem_definition[1]
else:
raise Error("STRIPS problem file is not structured properly")
domain_description = iterator.next()
#Check for issues in the problem's domain description
if (domain_description[0] == ":domain" and len(domain_description) == 2):
yield domain_description[1]
else:
raise Error("STRIPS problem file does not contain a domain description")
objects = iterator.next()
"""if requirements[0] == ":requirements":
yield requirements[1] #contains :typing
objects = iterator.next()
else:
objects = requirements """
if objects[0] == ":objects":
yield strip_types.parse_typed_list(objects[1:])
init = iterator.next()
else:
yield []
init = objects
if (init[0] != ":init"):
raise Error("STRIPS problem contains no init state")
initial = []
for fact in init[1:]:
initial.append(conditions.Atom(fact[0], fact[1:]))
yield initial
goal = iterator.next()
if (goal[0] == ":goal" and len(goal) == 2):
yield conditions.parse_condition(goal[1])
else:
raise Error("STRIPS problem contains no goal state")
def parse(pred_list):
name = pred_list[0]
args = strip_types.parse_typed_list(pred_list[1:])
return Predicate(name, args)
