python - 未绑定(bind)本地错误: local variable 'b' referenced before assignment

Question

我不断收到此错误，但我已在函数#Get data checkpoint size 中定义了局部变量。最初我认为这个错误可能是由于缩进造成的，但这对我来说也不起作用。

data_checkpoint_size = cclient.samples.list(meter_name ='checkpoint.size')
        data_checkpoint_length = cclient.samples.list(meter_name ='checkpoint.length')
        data_checkpoint_pause = cclient.samples.list(meter_name ='checkpoint.pause')
        data_cpu= cclient.samples.list(meter_name ='cpu')
        data_incomingbytes = cclient.samples.list(meter_name ='incoming.network.bytes')
        data_outgoingbytes = cclient.samples.list(meter_name ='outgoing.network.bytes')





      def counterVolume(data_cpu, data_incomingbytes, data_outgoingbytes, data_checkpoint_size, data_checkpoint_length, data_checkpoint_pause):
          for each in data_cpu:
            a = each.counter_volume
          for each in data_incomingbytes:
            b = each.counter_volume
          for each in data_outgoingbytes:
            c = each.counter_volume
          for each in data_checkpoint_size:
            d = each.counter_volume
          for each in data_checkpoint_length:
            e = each.counter_volume
          for each in data_checkpoint_pause:
            f = each.counter_volume
          pubnub.publish(channel='channel', message= {'cpu': a, 'incoming_bytes': b, 'outgoing_bytes': c, 'checkpoint_size': y, 'checkpoint_length': x, 'checkpoint_pause': z})


counterVolume(data_cpu, data_incomingbytes, data_outgoingbytes, data_checkpoint_size, data_checkpoint_length, data_checkpoint_pause)

Answer 1

for each in data_incomingbytes:
   b = each.counter_volume

如果data_incomingbytes为空怎么办？那么循环将不会运行，并且 b 将不会被分配。 Python 所提示的正是发生这种情况的可能性。无论循环是否运行，您都需要分配给 b (以及所有其他变量)。