pool.py 文件源码

def imap(self, func, iterable, chunksize=1):
        '''
        Equivalent of `itertools.imap()` -- can be MUCH slower than `Pool.map()`
        '''
        assert self._state == RUN
        if chunksize == 1:
            result = IMapIterator(self._cache)
            self._taskqueue.put((((result._job, i, func, (x,), {})
                         for i, x in enumerate(iterable)), result._set_length))
            return result
        else:
            assert chunksize > 1
            task_batches = Pool._get_tasks(func, iterable, chunksize)
            result = IMapIterator(self._cache)
            self._taskqueue.put((((result._job, i, mapstar, (x,), {})
                     for i, x in enumerate(task_batches)), result._set_length))
            return (item for chunk in result for item in chunk)