仿效占有欲量词 [英] Emulating possessive quantifiers

问题描述

是否有可能效仿占有欲量词（.NET不支持的话）用原子分组（或其他方式）？

Is it possible to emulate possessive quantifiers (.NET doesn’t support it) using atomic grouping (or in other way)?

请注意。我发现，（X + X +）++是可以换成（大于？（X + X +）+）Y ，但这仅仅是一个例子，我不知道是否总是 {东西} @ + 等于（大于{东西} @）（其中 @ 是一个量词）。

Note. I found that (x+x+)++y can be replaced with (?>(x+x+)+)y, but this is just an example and I don’t know whether always {something}@+ equals to (?>{something}@) (where @ is a quantifier).

推荐答案

是啊。我可以引述自己掌握，杰弗里·弗里德尔，从他的经典精通正防爆pressions（第3版）第142页< /一>：

Yup. May I quote the master himself, Jeffrey Friedl, from page 142 of his classic Mastering Regular Expressions (3rd Edition):

从某种意义上说，占有欲量词只是语法糖，因为它们可以用固化分组来模仿他，像这样 + 具有完全相同的结果为（大于？+），但一个聪明的实现可以优化占有欲量词超过原子团

"In one sense, possessive quantifiers are just syntactic sugar, as they can be mimicked with atomic grouping. Something like .++ has exactly the same result as (?>.+), although a smart implementation can optimize possessive quantifiers more than atomic grouping."

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