Python 正则表达式:如何对不立即开始的字符串进行负前瞻? [英] Python regex: how to do a negative lookahead with a string which don't start immediately?

问题描述

来自 https://docs.python.org/2/library/re.html#regular-expression-syntax :

(?!...)
如果 ... 与 next 不匹配，则匹配.这是一个否定的前瞻断言.例如，Isaac (?!Asimov) 将匹配 'Isaac ' 仅当它后面没有 'Asimov' 时.

(?!...)
Matches if ... doesn’t match next. This is a negative lookahead assertion. For example, Isaac (?!Asimov) will match 'Isaac ' only if it’s not followed by 'Asimov'.

但是如果 Isaac 和 Asimov 之间有一个或几个词怎么办?

But what to do if there is one or several words between Isaac and Asimov?

推荐答案

Isaac(?!.*Asimov)

对任何以阿西莫夫结尾的字符序列使用负前瞻.[\s\S] 或 DOTALL 标志可能适合在 . 中包含换行符.

Use a negative lookahead for any sequence of characters ending in Asimov. [\s\S] or the DOTALL flag may be appropriate if you want to include newlines in the ..

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