javascript regexp split including delimiter

Question

I want to split '9088{2}12{1}729' into [ "9088", "{2}12", "{1}729" ]

or even more useful to me: [ "9088", "2-12", "1-729" ]

tried:

'9088{2}12{1}729'.split(/\{[0-9]+\}/); => ["9088", "12", "729"]

also tried:

'9088{2}12{1}729'.match(/\{[0-9]+\}/); => ["{2}"]

I know it probably involved some other regexp string to split including delimiters.

Tried it in php, I guess you can do it in one line also.

preg_split( '/{/', preg_replace( '/}/', '-', "9088{2}12{1}729" ) )

Array ( [0] => 9088 [1] => 2-12 [2] => 1-729 )

Just have to wrap the replace function with split to get the preference order correct.

I think I like js more :)

Duplicate of http://stackoverflow.com/questions/4514144/js-string-split-without-removing-the-delimiters — Dilip Rajkumar, Nov 18 '14 at 06:12

Shiplu Mokaddim · Accepted Answer · 2012-11-14T22:28:28.287

4

even more useful to me: [ "9088", "2-12", "1-729" ]

It can be done using simple tricks!

"9088{2}12{1}729".replace(/\}/g,'-').split(/\{/g)

// ["9088", "2-12", "1-729"]

edited Nov 14 '12 at 22:28

answered Nov 14 '12 at 20:22

Shiplu Mokaddim

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Do you have a bottle of awesomeness by your desk :) Thank you. – Bruce Lim Nov 14 '12 at 20:26

Mike Samuel · Answer 2 · 2012-11-14T20:41:35.087

You can use a simple zero-width positive lookahead with /(?={)/:

'9088{2}12{1}729'.split(/(?=\{)/);  // => ["9088","{2}12","{1}729"]

The "zero-width" part means that the actual matched text is the empty string so the split throws away nothing, and the lookahead means it matches just before the contained pattern, so /(?=\{)/ matches the empty strings between characters where indicated by an arrow:

9 0 8 8 { 2 } 1 2 { 1 } 7 2 9
       ↑         ↑

You can then use Array.prototype.map to convert from {1}2 form to 1-2 form.

'9088{2}12{1}729'.split(/(?=\{)/)
    .map(function (x) { return x.replace('{', '').replace('}', '-'); });

yields

["9088","2-12","1-729"]

javascript regexp split including delimiter

2 Answers2