def impl_or(engine, call1, call2, continuation):
oldstate = engine.heap.branch()
try:
return engine.call(call1, continuation)
except error.UnificationFailed:
engine.heap.revert(oldstate)
return engine.call(call2, continuation, choice_point=False)
def impl_or(engine, call1, call2, continuation):
oldstate = engine.heap.branch()
try:
return engine.call(call1, continuation)
except error.UnificationFailed:
engine.heap.revert(oldstate)
return engine.call(call2, continuation, choice_point=False)
def impl_not(engine, call):
try:
try:
engine.call(call)
except error.CutException, e:
engine.continue_after_cut(e.continuation)
except error.UnificationFailed:
return None
raise error.UnificationFailed()
def impl_if(engine, if_clause, then_clause, continuation):
oldstate = engine.heap.branch()
try:
engine.call(if_clause)
except error.UnificationFailed:
engine.heap.revert(oldstate)
raise
return engine.call(helper.ensure_callable(then_clause), continuation,
choice_point=False)
def impl_not(engine, call):
try:
try:
engine.call(call)
except error.CutException, e:
engine.continue_after_cut(e.continuation)
except error.UnificationFailed:
return None
raise error.UnificationFailed()
def impl_if(engine, if_clause, then_clause, continuation):
oldstate = engine.heap.branch()
try:
engine.call(if_clause)
except error.UnificationFailed:
engine.heap.revert(oldstate)
raise
return engine.call(helper.ensure_callable(then_clause),
continuation,
choice_point=False)
def impl_findall(engine, template, goal, bag):
oldstate = engine.heap.branch()
collector = FindallContinuation(template)
try:
engine.call(goal, collector)
except error.UnificationFailed:
engine.heap.revert(oldstate)
result = term.Atom.newatom("[]")
for i in range(len(collector.found) - 1, -1, -1):
copy = collector.found[i]
d = {}
copy = copy.copy(engine.heap, d)
result = term.Term(".", [copy, result])
bag.unify(result, engine.heap)
def impl_and(engine, call1, call2, continuation):
if not isinstance(call2, term.Var) and not isinstance(
call2, term.Callable):
error.throw_type_error('callable', call2)
and_continuation = AndContinuation(call2, continuation)
return engine.call(call1, and_continuation, choice_point=False)
def _call(self, engine):
next_call = self.next_call.dereference(engine.heap)
next_call = helper.ensure_callable(next_call)
return engine.call(next_call, self.continuation, choice_point=False)
def impl_call(engine, call, continuation):
try:
return engine.call(call, continuation)
except error.CutException, e:
return e.continuation.call(engine, choice_point=False)
def impl_once(engine, clause, continuation):
engine.call(clause)
return continuation.call(engine, choice_point=False)
def impl_and(engine, call1, call2, continuation):
if not isinstance(call2, term.Var) and not isinstance(call2, term.Callable):
error.throw_type_error('callable', call2)
and_continuation = AndContinuation(call2, continuation)
return engine.call(call1, and_continuation, choice_point=False)
def _call(self, engine):
next_call = self.next_call.dereference(engine.heap)
next_call = helper.ensure_callable(next_call)
return engine.call(next_call, self.continuation, choice_point=False)
