python 判空 is None 和 if not None 对比
Thanks for comments.
I have tested the perform between these:
import timeit
def using_is_none(variable):
return variable is None
def using_if_not_none(variable):
return not variable
variable = None
print("Using 'is None':", timeit.timeit(lambda: using_is_none(variable), number=1000000))
print("Using 'if not None':", timeit.timeit(lambda: using_if_not_none(variable), number=1000000))
output:
jn@ubuntu:/code $ py311 /code/jupyter/test.py
Using 'is None': 0.09608164499513805
Using 'if not None': 0.057769965002080426
'if not None' have better performance(In the loop 1000000 times)
Compare to 'is None', use 'if not' have bonus:
Convert var='False', '0' and other empty data structure to set(), which respect the following legacy codes.
So I prefer to keep it.