Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

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

if statement - Python "if X == Y and Z" syntax

Does this:

if key == "name" and item:

mean the same as this:

if key == "name" and if key == "item":

If so, I'm totally confused about example 5.14 in Dive Into Python. How can key be equal to both "name" and item? On the other hand, does "and item" simply ask whether or not item exists as a variable?

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 Answer

0 votes
by (71.8m points)

if key == "name" and item: means if (key == "name") and (item evaluates to True).

Keep in mind that (item evaluates to True) is possible in several ways. For example if (key == "name") and [] will evaluate to False.


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 OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

2.1m questions

2.1m answers

60 comments

57.0k users

...