<分区>
我想确保 d1-d2
不会在第一个示例的每次迭代中重新计算。我怎样才能检查这个?
>>> def f(d1: Counter, d2: Counter):
... for reason, count in (d1 - d2).items():
... print(reason, count)
...
>>> def f2(d1: Counter, d2: Counter):
... diff = (d1 - d2).items()
... for reason, count in diff:
... print(reason, count)
有什么建议在可读性和性能方面更像 pythonic 吗?