and not search pattern

Question

I created vim search pattern to find bad status codes:

   / [45][0-9][0-9]

It can find 504 or 499 or 404 (space before and after each number)

But I don't want it to find 404. How to change my search pattern to make it skip 404?

With the given information there's no way for us to create a regex matching your needs. What kind of status codes do you want to match? — Vince, Oct 09 '13 at 13:17

score 7 · Accepted Answer · edited May 23 '17 at 11:57

7

Using a negative look-ahead for that number:

/\(.*404\)\@![45]\d\{2\}

UPDATE: Thanks to Karoly Horvath to point out that this regex could fail with some numbers in the same line. Much better:

/\(404\)\@![45]\d\{2\}

Another way with a negative look-behind after the match:

/[45]\d\{2\}\(404\)\@<!

edited May 23 '17 at 11:57

Community

answered Oct 09 '13 at 13:18

Birei

1

Does vim support lookahead in regexes? Isn't that a POSIX engine? – Tim Pietzcker Oct 09 '13 at 13:19
@TimPietzcker It does. – devnull Oct 09 '13 at 13:20
1

@TimPietzcker: Yes. It supports them. `Vim` regex flavour is very powerfull. You can look at it with `:help regex` – Birei Oct 09 '13 at 13:20
don't use `.*`, that prevents any matches in a line which contains 404. – Karoly Horvath Oct 09 '13 at 13:25
@KarolyHorvath: You are right, but what passed my test is that I put the `404` as the first number, like: `one 404 two 504`. And it matches the `504`, but not in `one 504 two 404`. – Birei Oct 09 '13 at 13:30
@Birei with required spaces before and after status codes: `/ [45]\d\{2\} \( 404 \)\@ – Maxim Yefremov Oct 09 '13 at 13:32
@KarolyHorvath: Nothing at all. I can rid of it. Sorry that I didn't understand you the first time :-) – Birei Oct 09 '13 at 13:41

Kobi · Answer 2 · 2013-10-09T13:26:27.947

2

5[0-9][0-9]|4[1-9][0-9]|40[0-35-9]

The old-school pattern is:

I hope you don't have other black-listed codes, because this will get ugly very quickly.

edited Oct 09 '13 at 13:26

answered Oct 09 '13 at 13:19

Kobi

I'm probably wrong about the lookahead: http://stackoverflow.com/questions/18391665/vim-positive-lookahead-regex . I'll remove that comment. – Kobi Oct 09 '13 at 13:25

2 Answers2