Ruby中的正则表达式负向后退似乎不起作用 [英] Regex negative lookbehind in Ruby doesn't seem to work

问题描述

进行参数解析器.我想将字符串拆分为定界符为", "的数组，除非以"|"开头.这意味着字符串

Making an argument parser. I want to split a string into an array where the delimiter is ", " except when preceded by "|". That means string

"foo, ba|, r, arg"

应该导致

`["foo", "ba|, r", "arg"]`

我正在尝试使用此正则表达式:(?<!\|),，可在 http://regexhero.net/tester/中使用但是当我尝试

I'm trying to use this regex: (?<!\|), which works in http://regexhero.net/tester/ but when I try

args.split(/(?<!\|), /)

在红宝石中，我得到一个错误:undefined (?...) sequence: /(?<!\|), /

in ruby, I get an error: undefined (?...) sequence: /(?<!\|), /

推荐答案

Ruby的regex引擎不支持lookbehind(尚未).

Ruby's regex engine doesn't support lookbehind (yet).

您需要切换到1.9或使用 Oniguruma .

You'd need to switch to 1.9 or use Oniguruma.

如果这不是一个选项，则可以搜索|,并将其替换为某种标记.说完一切之后，放回|,.

If that's not an option, you can search for |, and replace it with some sort of marker. After all is said and done, put the |, back.

您也可以尝试以下正则表达式:

You can also try a regex like:

/(?:[^|]), /

但是(?:[^|])显然不是零宽度的，这意味着之后您需要做一些额外的工作.

But obviously the (?:[^|]) is not zero-width, which means you'll need to do some extra work afterwards.

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