匹配CSS不是评论

Question

I know there's been a lot of related questions but none seems to fill my specific needs.

Basically, I need to match CSS code that is not a comment.
I've tried this (input first)

foo

(?<!/\*)foo

but it fails not to match the following:

/* foo

and

/* comment foo

Also, (?<!/\\*\\s*)foo will cause an error.

PS For those who may ask, I don't need to care about strings.

Answer 1

If the CSS you are working with is "valid" and you ignore string syntax, you could use a cheap trick like this:

foo(?!(?:[^/*]++|/(?!\*)|\*(?!/))*+\*/)

What it does is check that foo isn't followed by a */ (without any /* before it).

(You can remove the possessive quantifiers + , if your PHP version is outdated and doesn't support them.)