有没有办法对未定义的变量进行 while 循环？（我该如何重写，Python）

Question

我想做一个 while 循环，直到用户在输入中不输入任何内容。

这是我目前可以使用的，但我想删除 answer = None 实例化。

def answer_as_ul(question, input_prefix='• '):
    print(question)
    answer_list = list()
    answer = None
    while answer != '':
        answer = input(input_prefix)
        answer_list.append(answer) if answer else None
    return answer_list

有没有办法在此处删除 answer = None 并保留功能？

Answer 1

使用下面的代码。我还为更多 Pythonic 代码添加了一些小调整：

def answer_as_ul(question, input_prefix='• '):
    print(question)
    answer_list = []
    while True:
        answer = input(input_prefix)
        if not answer: break
        answer_list.append(answer)
    return answer_list

Answer 2

也许像这样，但差别不大:

def answer_as_ul(question, input_prefix='• '):
    print(question)
    answer_list = list()
    while True:
        answer = input(input_prefix)
        if answer: break  
        else: answer_list.append(answer)
    return answer_list

Answer 3

感谢 @jonsharpe's beautiful solution using Python 3.8's walrus operator 我找到了答案:

def answer_as_ul(question, input_prefix='• '):
    print(question)
    answer_list = list()
    while answer := input(input_prefix):
        answer_list.append(answer)
    return answer_list

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有没有办法对未定义的变量进行 while 循环？（我该如何重写，Python）