python regex: match any style line break

Question

Is there a way to match a line break independently of system? i.e. match both \n and \r\n. The only thing I can think of is \r?\n which just feels clunky.

The reason I want to do this is

if I need to match 2 in a row, \n\n no longer works and
if I match \n, then the preceding \r will still exist and I would have to strip it off or it could lead to problems later

Do you need a regular expression or would reading a file line by line (with universal readlines) suffice? — Jean Hominal, Feb 01 '17 at 20:29
@JeanHominal the point is to come up with something I can use in a larger regex. — ewok, Feb 01 '17 at 20:30

Sarath Sadasivan Pillai · Answer 1 · 2017-02-01T20:38:08.700

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This should be good for cross-platform line break

regex = '(\r\n?|\n)+'

edited Feb 01 '17 at 20:38

answered Feb 01 '17 at 20:28

Sarath Sadasivan Pillai

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are you sure of the `r` prefix in that case? – Jean-François Fabre Feb 01 '17 at 20:28
Yes, r makes sure the raw text – Sarath Sadasivan Pillai Feb 01 '17 at 20:29
Yes, works (although works without too) – Jean-François Fabre Feb 01 '17 at 20:31
@Jean-FrançoisFabre updated comment :D – Sarath Sadasivan Pillai Feb 01 '17 at 20:34

GantTheWanderer · Answer 2 · 2017-02-01T20:31:11.967

1

Wouldn't this get all groups of adjacent \r and \n characters regardless of order or amount?

Edited per comments:

[\r\n]+

edited Feb 01 '17 at 20:31

answered Feb 01 '17 at 20:27

GantTheWanderer

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`[\r\n]*` will match an empty string and empty strings before any non-matching texts. – Wiktor Stribiżew Feb 01 '17 at 20:28
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@WiktorStribiżew that can be fixed with `+`: `[\r\n]+` – ewok Feb 01 '17 at 20:28

python regex: match any style line break

2 Answers2