def get_previously_sent_item(self, menu_system):
"""
Get the item that was previously sent to the client. It is needed to
be able to determine what question the incoming answer is answering.
"""
previous_index = self.session_manager.data.get("previous_index", None)
# we can't check for just previous_index, since zero resolves to False
# in an if statement
if previous_index >= 0:
return copy_generator(menu_system.stack[previous_index - 1])
def case(*cases):
"""Returns the first prompt for which the test function returns True"""
while True:
ms, session = yield
for test, prompt in cases:
if test(ms, session):
prompt = copy_generator(prompt)
prompt.next()
question = prompt.send((ms, session))
yield question
answer = yield
prompt.next()
validated_answer = prompt.send(answer)
yield validated_answer
yield False, False # no message and not end of menu
def next(self):
"""
Proceed to the next coroutine in the stack
"""
# If we've reached the end of the stack stop iterating
if self.__iter_index > len(self.stack):
raise StopIteration
# If we're at the last time there isn't a next item to send
# to the client so return None
if self.__iter_index == len(self.stack):
next_item = None
else:
# otherwise, copy the coming coroutine, the index is always
# one ahead of where we are actually at.
next_item = copy_generator(self.stack[self.__iter_index])
# increment, ready for next round
self.__iter_index += 1
return self.__iter_index, next_item
