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 True 或 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 ，如下所示：

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

除非不起作用。我知道我可以这样做：

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

但这相当丑陋 - 特别是如果这些if语句正在进行中在我的代码中发生了很多。有没有什么方法可以用更清晰的语法进行评估（比如第一个例子）？

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< a href =https://softwareengineering.stackexchange.com/questions/12807/make-a-big-deal-out-of-true>永远不要用 == True测试布尔变量（或 == False ）。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 任何 （在相关问题中，其堂兄 全部 ）：

or use any (and in related problems its cousin all):

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

或使用Python的传递性比较：

or use Python's transitive comparisons:

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

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