- def __len__(self):
- """len(:class:`Threads`) returns the number of contained Threads
-
- .. note:: As this iterates over the threads, we will not be able to
- iterate over them again! So this will fail::
-
- #THIS FAILS
- threads = Database().create_query('').search_threads()
- if len(threads) > 0: #this 'exhausts' threads
- # next line raises :exc:`NotInitializedError`!!!
- for thread in threads: print thread
- """
- if not self._threads:
- raise NotInitializedError()
-
- i = 0
- # returns 'bool'. On out-of-memory it returns None
- while self._valid(self._threads):
- self._move_to_next(self._threads)
- i += 1
- # reset self._threads to mark as "exhausted"
- self._threads = None
- return i
-