From: William James <w_a_x_man@...>
Date: 2005-02-19T11:19:45+09:00
Subject: Re: Regexp help - Negative lookahead before across word boundaries

Phrogz wrote:
> Given a string like this:
> "this.position.x = foo.bar.whee * jim.jam - yow / this.jorgle"
>
> I want to match all the global identifiers which are not 'this', and
I
> 'need' to do so without consuming any other characters.
>
> This regexp:
>   /[^.]\b(?!this)[a-zA-Z_]\w*\b/
> works, but it consumes the preceding character.
>

s="bar this.position.x = foo.bar.whee * jim.jam - yow / this.jorgle"
p s.scan( /(?:^|[^.])\b(?!this)([a-zA-Z_]\w*)\b/ ).flatten

produces

["bar", "foo", "jim", "yow"]