[Python-Dev] Finding overlapping matches with re assertions: bug or feature? (original) (raw)
Paul Moore p.f.moore at gmail.com
Fri Nov 15 10:47:56 CET 2013
- Previous message: [Python-Dev] Finding overlapping matches with re assertions: bug or feature?
- Next message: [Python-Dev] Finding overlapping matches with re assertions: bug or feature?
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
On 15 November 2013 06:48, Tim Peters <tim.peters at gmail.com> wrote:
Is that a feature? Or an accident? It's very surprising to find a non-empty match inside an empty match (the outermost lookahead assertion).
Personally, I would read (?=(R))" as finding an empty match at a point where R starts. There's no implication that R is in any sense "inside" the match.
(?=(<\w\w\w\w\w\w)\w\w\w) finds the first 3 characters of words that are 6 or more characters long. Once again, the lookahead extends beyond the extent of the main match.
It's obscure and a little bizarre, but I'd say its intended and a logical consequence of the definitions.
Paul
- Previous message: [Python-Dev] Finding overlapping matches with re assertions: bug or feature?
- Next message: [Python-Dev] Finding overlapping matches with re assertions: bug or feature?
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]