➜
This issue tracker has been migrated to GitHub,
and is currently read-only.
For more information,
see the GitHub FAQs in the Python's Developer Guide.
Created on 2022-02-22 10:23 by HeRaNO, last changed 2022-04-11 14:59 by admin. This issue is now closed.
| Files | ||||
|---|---|---|---|---|
| File name | Uploaded | Description | Edit | |
| match.py | HeRaNO, 2022-02-22 10:23 | |||
| Messages (3) | |||
|---|---|---|---|
| msg413700 - (view) | Author: Heran Yang (HeRaNO) | Date: 2022-02-22 10:23 | |
I'm using `re.fullmatch` to match a string that only contains 0 and 1. The regular expression is: (0+|1(01*0)*1)+ It runs rather slow with Python 3.7, but when I try using regex in C++, with std::regex_constants::__polynomial, it works well. Would someone take a look at it? Thx. |
|||
| msg413708 - (view) | Author: Matthew Barnett (mrabarnett) *  |
Date: 2022-02-22 14:36 | |
The expression is a repeated alternative where the first alternative is a repeat. Repeated repeats can result in a lot of attempts and backtracking and should be avoided.
Try this instead:
(0|1(01*0)*1)+
|
|||
| msg413730 - (view) | Author: Serhiy Storchaka (serhiy.storchaka) *  |
Date: 2022-02-22 18:17 | |
The re module does not support features corresponding to std::regex_constants::__polynomial in C++. Rewrite your regular expression or try to use alternative regex implementations (for example wrappers around the re2 library or C++ regex library). |
|||
| History | |||
|---|---|---|---|
| Date | User | Action | Args |
| 2022-04-11 14:59:56 | admin | set | github: 90981 |
| 2022-02-22 18:17:22 | serhiy.storchaka | set | status: open -> closed nosy: + serhiy.storchaka messages: + msg413730 resolution: wont fix stage: resolved |
| 2022-02-22 14:36:28 | mrabarnett | set | messages: + msg413708 |
| 2022-02-22 10:23:02 | HeRaNO | create | |