Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
183 views
in Technique[技术] by (71.8m points)

python - ([False, True] and [True, True]) evaluates to [True, True]

I have observed the following behavior in python 3:

>>> ([False, True] and [True, True])
[True, True]

>>> ([False, True] or [True, True])
[False, True]

I was expecting exactly the opposite:

[False, True] and [True, True] = [False and True, True and True] = [False, True]
[False, True] or [True, True] = [False or True, True or True] = [True, True]

How does the observed behavior makes sense and how can I achieve the desired behavior?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

Each list is being evaluated as a whole. [False, True] is True, and so is [True, True] because only an empty list is False.

and returns the last True element, but or returns the first one.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...