regular expression to match pipe separated strings with pipe escaping

Question

I'd like to get the single strings of a pipe-separated string, with "pipe escaping" support, e.g.:

fielda|field b |field\|with\|pipe\|inside

would get me:

array("fielda", "field b ", "field|with|pipe|inside")

How would I reach that goal with a regular expression?

What language are you using? Chances are that the language already supports something like this for you with a CSV parsing function or module. — Andy Lester, Jan 28 '15 at 21:09

score 6 · Accepted Answer · answered Jan 28 '15 at 19:37

6

Split  by this (?<!\\)\|

See demo.The lookbehind makes sure | is not after \.

https://regex101.com/r/pM9yO9/15

answered Jan 28 '15 at 19:37

vks

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score 1 · Answer 2 · answered Jan 28 '15 at 19:43

1

This should work too:

((?:[^\\|]+|\\\|?)+)

The regex will capture everything up to a single | (including \|)

DEMO

answered Jan 28 '15 at 19:43

Enissay

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score 0 · Answer 3 · answered Jan 29 '15 at 13:03

0

An other way with php, using strtr that replace \| with a placeholder:

$str = 'field a|field b|field\|with\|pipe\|inside';
$str = strtr($str, array('\|' => '#'));
$result = array_map(function ($i) {
    return strtr($i, '#', '|');
}, explode('|', $str));

answered Jan 29 '15 at 13:03

Casimir et Hippolyte

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score 0 · Answer 4 · answered Jan 27 '20 at 22:16

You may match these items with

(?:[^\\|]|\\[\s\S])+

See the regex demo.

NOTE: If you need to split on a character other than | just replace it within the first negated character class, [^\\|]. Just note that you will have to escape ] (unless it is placed right after [^) and - (if not at the start/end of the class).

The [\s\S] can be replaced with a . in many engines and pass the appropriate option to make it match across line endings.

See the regex graph:

JS demo:

console.log(
   "fielda|field b |field\\|with\\|pipe\\|inside".match(/(?:[^\\|]|\\[\s\S])+/g)
)
// =>  ["fielda", "field b ", "field\|with\|pipe\|inside"]

regular expression to match pipe separated strings with pipe escaping

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