JavaScript regex match [[quote][/quote]]

Question

var quote = 'some text here [[quote=bob]This is some text bob wrote[/quote]] other text here';

I'm trying to get [[quote=bob]This is some text bob wrote[/quote]].

I was using: match(/[[quote=(.*?)](.*?)[/quote]]/)[1]

but it gives me some text here [[quote=bob]This is some text bob wrote[/quot

Be aware of [You can't parse (X)HTML with regex](http://stackoverflow.com/a/1732454/1529630). It may be applicable to your case too, if your language is complex enough. — Oriol, Nov 07 '14 at 18:17
@j08691 Yes, but that seems suspiciously close to html. I only wanted to warn, just in case. — Oriol, Nov 07 '14 at 18:24
I'm taking text and translating it into html - just like people see on many phpbb forums — Shazboticus S Shazbot, Nov 07 '14 at 18:24
The same caveats apply to bbcode. Changing the brackets from angled to square doesn't change the syntactic complexity. — Mark Reed, Nov 07 '14 at 18:25

Johan Karlsson · Accepted Answer · 2014-11-07T18:26:38.777

3

Try this:

var quote = 'some text here [[quote=bob]This is some text bob wrote[/quote]] other text here';

console.log( quote.match(/(\[\[quote=(.*?)\](.*?)\[\/quote\]\])/) );
// [1] => "[[quote=bob]This is some text bob wrote[/quote]]"
// [2] => "bob"
// [3] => "This is some text bob wrote"

edited Nov 07 '14 at 18:26

answered Nov 07 '14 at 18:19

Johan Karlsson

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Using `.*` here is not safe as I stated in my answer. Regex will find the longest possible match and so using a different string I get bad results : `'some text here [[quote=bob]This is some text bob wrote[/quote]] other text here[/quote]]'.match(/.*(\[\[quote=.*?\].*?\[\/quote\]\])/); ` gives : `["some text here [[quote=bob]This is some text bob wrote[/quote]]","[[quote=bob]This is some text bob wrote[/quote]]"]` – Johnride Nov 07 '14 at 18:26
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@Johnride `.*` does that, not `.*?`. – Johan Karlsson Nov 07 '14 at 18:32
1

That's one I didn't know about. `?` turns `+` and `*` into non-greedy matches. Nice one. Here take my upvote. – Johnride Nov 07 '14 at 18:38
This still fails on nested quotes, e.g. this: "[[quote=foo]some text here [[quote=bob]This is some text bob wrote[/quote]] other text here[/quote]]" (see http://regexr.com/39sa0 for a live example) – Jesse W at Z - Given up on SE Nov 07 '14 at 18:40
@JesseWatZ Then it becomes much less straigthforward. Using recursive backrefs or something like that is required. I like regexes, it's a world of ever-ending improving and learning. Mine works a little better with nested quotes but has to be used recursively deleting the previous match. http://regexr.com/39sa3. Mine fails if the quote contains a [ though. – Johnride Nov 07 '14 at 18:43

Johnride · Answer 2 · 2014-11-07T18:34:53.953

The problem here is that [ is a reserved character in regular expressions so you must escape it to use it as a "regular" character.

Here is a start for you, this will match [quote=bob] from your variable quote.

quote.match(/\[quote=[a-z]*\]/)

Here is the complete, correct and safe version.

string.match(/\[quote=[a-z]*\]([^\[]*)\[\/quote\]/)

Which will return the proper string including the surrounding [quote] tags as first result and only the inner string as second result.

I also used the [a-z] character class as you don't want to match anything after the = character.

JavaScript regex match [[quote][/quote]]

2 Answers2