python列表理解中的if/else [英] If/else in python list comprehension

问题描述

我想根据传递的参数从文件中返回随机单词.但是，如果参数与任何内容都不匹配，我就不希望返回任何内容.我的方法如下:

I would like to return random word from file, based on passed argument. But if the argument doesn't match anythning I dont want to return anything. My method looks like:

def word_from_score(self,score):
    print(random.choices([word for word in self.file if sum([LETTER_SCORES[letter] for letter in word ]) == score]))

它基于命令行中传递的参数从文件中返回正确的单词，但是如果参数不匹配，我将不返回任何内容，如''.我如何在此声明中添加其他内容?

It returns the correct word from file based on passed argument in command line, but if the argument doesnt match, i want to return nothing, like ''. How could I add else to this statement?

推荐答案

应为:

def word_from_score(self,score):
    print(random.choices([(word if sum([LETTER_SCORES[letter] for letter in word ]) == score else "") for word in self.file]))

(... if ... else ...)实际上是三元运算符，不是周围列表理解的一部分.

The (... if ... else ...) is actually the ternary operator and not part of the surrounding list comprehension.

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