在一个“if"语句中评估多个变量? [英] Evaluate multiple variables in one 'if' statement?

问题描述

假设我有一堆变量，它们要么是 True，要么是 False.我想在一个 if 语句中评估一组这些变量，看看它们是否都是 False 像这样:

Say I have a bunch of variables that are either True or False. I want to evaluate a set of these variables in one if statement to see if they are all False like so:

if var1, var2, var3, var4 == False:
    # do stuff

除非那不起作用.我知道我可以做到这一点:

Except that doesn't work. I know I can do this:

if var1 == False and var2 == False and var3 == False and var4 == False:
    # do stuff

但这相当难看 - 特别是如果这些 if 语句将在我的代码中出现很多.有没有什么方法可以用更简洁的语法(如第一个示例)进行此评估?

But that's fairly ugly - especially if these if statements are going to occur a lot in my code. Is there any sort of way I can do this evaluation with a cleaner syntax (like the first example)?

推荐答案

你应该永远不要使用 == True(或 == False) 测试布尔变量.相反，要么写:

You should never test a boolean variable with == True (or == False). Instead, either write:

if not (var1 or var2 or var3 or var4):

或使用 any(以及相关的它的表亲问题 all):

if not any((var1, var2, var3, var4)):

或使用 Python 的传递比较:

or use Python's transitive comparisons:

if var1 == var2 == var3 == var4 == False:

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