+ The existence of this function makes 'if Threads: foo' work, as
+ that will implicitely call len() exhausting the iterator if
+ __nonzero__ does not exist. This function makes `bool(Threads())`
+ work repeatedly.
+
+ :return: True if there is at least one more thread in the
+ Iterator, False if not. None on a "Out-of-memory" error.
+ """
+ return self._threads is not None and \
+ self._valid(self._threads) > 0
+
+ _destroy = nmlib.notmuch_threads_destroy
+ _destroy.argtypes = [NotmuchThreadsP]
+ _destroy.argtypes = None