def impl_arg(engine, first, second, third, continuation):
if isinstance(second, term.Var):
error.throw_instantiation_error()
if isinstance(second, term.Atom):
raise error.UnificationFailed()
if not isinstance(second, term.Term):
error.throw_type_error("compound", second)
if isinstance(first, term.Var):
for i in range(len(second.args)):
arg = second.args[i]
oldstate = engine.heap.branch()
try:
third.unify(arg, engine.heap)
first.unify(term.Number(i + 1), engine.heap)
return continuation.call(engine, choice_point=True)
except error.UnificationFailed:
engine.heap.revert(oldstate)
raise error.UnificationFailed()
elif isinstance(first, term.Number):
num = first.num
if num == 0:
raise error.UnificationFailed
if num < 0:
error.throw_domain_error("not_less_than_zero", first)
if num > len(second.args):
raise error.UnificationFailed()
arg = second.args[num - 1]
third.unify(arg, engine.heap)
else:
error.throw_type_error("integer", first)
return continuation.call(engine, choice_point=False)
def ensure_callable(var):
if isinstance(var, term.Var):
error.throw_instantiation_error()
elif isinstance(var, term.Callable):
return var
else:
error.throw_type_error("callable", var)
def ensure_callable(var):
if isinstance(var, term.Var):
error.throw_instantiation_error()
elif isinstance(var, term.Callable):
return var
else:
error.throw_type_error("callable", var)
def impl_arg(engine, first, second, third, continuation):
if isinstance(second, term.Var):
error.throw_instantiation_error()
if isinstance(second, term.Atom):
raise error.UnificationFailed()
if not isinstance(second, term.Term):
error.throw_type_error("compound", second)
if isinstance(first, term.Var):
for i in range(len(second.args)):
arg = second.args[i]
oldstate = engine.heap.branch()
try:
third.unify(arg, engine.heap)
first.unify(term.Number(i + 1), engine.heap)
return continuation.call(engine, choice_point=True)
except error.UnificationFailed:
engine.heap.revert(oldstate)
raise error.UnificationFailed()
elif isinstance(first, term.Number):
num = first.num
if num == 0:
raise error.UnificationFailed
if num < 0:
error.throw_domain_error("not_less_than_zero", first)
if num > len(second.args):
raise error.UnificationFailed()
arg = second.args[num - 1]
third.unify(arg, engine.heap)
else:
error.throw_type_error("integer", first)
return continuation.call(engine, choice_point=False)
def convert_to_str(obj):
if isinstance(obj, term.Var):
error.throw_instantiation_error()
if isinstance(obj, term.Atom):
return obj.name
elif isinstance(obj, term.Number):
return str(obj.num)
elif isinstance(obj, term.Float):
return str(obj.floatval)
error.throw_type_error("atomic", obj)
def convert_to_str(obj):
if isinstance(obj, term.Var):
error.throw_instantiation_error()
if isinstance(obj, term.Atom):
return obj.name
elif isinstance(obj, term.Number):
return str(obj.num)
elif isinstance(obj, term.Float):
return str(obj.floatval)
error.throw_type_error("atomic", obj)
def impl_univ(engine, first, second):
if not isinstance(first, term.Var):
if isinstance(first, term.Term):
l = [term.Atom(first.name)] + first.args
else:
l = [first]
u1 = helper.wrap_list(l)
if not isinstance(second, term.Var):
u1.unify(second, engine.heap)
else:
u1.unify(second, engine.heap)
else:
if isinstance(second, term.Var):
error.throw_instantiation_error()
else:
l = helper.unwrap_list(second)
head = l[0]
if not isinstance(head, term.Atom):
error.throw_type_error("atom", head)
term.Term(head.name, l[1:]).unify(first, engine.heap)
def impl_univ(engine, first, second):
if not isinstance(first, term.Var):
if isinstance(first, term.Term):
l = [term.Atom(first.name)] + first.args
else:
l = [first]
u1 = helper.wrap_list(l)
if not isinstance(second, term.Var):
u1.unify(second, engine.heap)
else:
u1.unify(second, engine.heap)
else:
if isinstance(second, term.Var):
error.throw_instantiation_error()
else:
l = helper.unwrap_list(second)
head = l[0]
if not isinstance(head, term.Atom):
error.throw_type_error("atom", head)
term.Term(head.name, l[1:]).unify(first, engine.heap)
def impl_functor(engine, t, functor, arity):
if helper.is_atomic(t):
functor.unify(t, engine.heap)
arity.unify(term.Number(0), engine.heap)
elif isinstance(t, term.Term):
functor.unify(term.Atom(t.name), engine.heap)
arity.unify(term.Number(len(t.args)), engine.heap)
elif isinstance(t, term.Var):
if isinstance(functor, term.Var):
error.throw_instantiation_error()
a = helper.unwrap_int(arity)
if a < 0:
error.throw_domain_error("not_less_than_zero", arity)
else:
functor = helper.ensure_atomic(functor)
if a == 0:
t.unify(helper.ensure_atomic(functor), engine.heap)
else:
name = helper.unwrap_atom(functor)
t.unify(term.Term(name, [term.Var() for i in range(a)]),
engine.heap)
def impl_functor(engine, t, functor, arity):
if helper.is_atomic(t):
functor.unify(t, engine.heap)
arity.unify(term.Number(0), engine.heap)
elif isinstance(t, term.Term):
functor.unify(term.Atom(t.name), engine.heap)
arity.unify(term.Number(len(t.args)), engine.heap)
elif isinstance(t, term.Var):
if isinstance(functor, term.Var):
error.throw_instantiation_error()
a = helper.unwrap_int(arity)
if a < 0:
error.throw_domain_error("not_less_than_zero", arity)
else:
functor = helper.ensure_atomic(functor)
if a == 0:
t.unify(helper.ensure_atomic(functor), engine.heap)
else:
name = helper.unwrap_atom(functor)
t.unify(
term.Term(name, [term.Var() for i in range(a)]),
engine.heap)
def eval_arithmetic(self, engine):
self = self.dereference(engine.heap)
if isinstance(self, Var):
error.throw_instantiation_error()
return self.eval_arithmetic(engine)
def eval_arithmetic(self, engine):
self = self.dereference(engine.heap)
if isinstance(self, Var):
error.throw_instantiation_error()
return self.eval_arithmetic(engine)
