如果它满足python中的某些条件，我想拆分字符串答案

【问题标题】：I want to split the string with if it satisfies some conditions in python如果它满足python中的某些条件，我想拆分字符串
【发布时间】：2020-10-19 03:05:18
【问题描述】：

my_str = 'According to the teacher, "He never believed what I said. He ran away." And I think he did indeed. I tried to find him, but I could not.'

结果应该是：

['According to the teacher, "He never believed what I said. He ran away." And I think he did indeed.', 'I tried to find him, but I could not.']

在这个字符串中，我想用 .(dot) 分割它但是，如果 .(dot) 在 " "(quotation) 中，我不想拆分它

我该如何使用re.split()？

【问题讨论】：

标签： python regex string split

【解决方案1】：

考虑使用.findall，与：

(?:[^."]+"[^"]+")*[^."]+\.

https://regex101.com/r/d400Ut/1

(?:[^."]+"[^"]+")* - 重复 0 次或更多次：
- [^."]+ 非". 字符，后跟
- "[^"]+" - 引号内的字符
[^."]+\. - 匹配非." 字符，后跟句点

matches = re.findall(r'(?:[^."]+"[^"]+")*[^."]+\.', my_str)

【讨论】：

【解决方案2】：

不幸的是，这里没有适用于所有字符串的答案。您所描述的逻辑类型需要的不仅仅是正则表达式所使用的“常规”语法。您必须创建自己的自定义逻辑，例如：

def custom_split_string(s: str) -> List[str]:
    output = []
    in_quote = False
    word = []
    for ch in s:
        word.append(ch)
        if ch == "." and not in_quote:
            output.append(''.join(word))
            word.clear()
        elif ch == '"':
            in_quote = not in_quote  # assume no nested quotes
    return output

my_str = 'According to the teacher, "He never believed what I said. He ran away." And I think he did indeed. I tried to find him, but I could not.'

expected_output = ['According to the teacher, "He never believed what I said. He ran away." And I think he did indeed.', ' I tried to find him, but I could not.']

assert custom_split_string(my_str) == expected_output

【讨论】：