What is this regex doing?

Question

I thought this regex was about turning words into an array, but I get null as a result

when I want to get the second word from "facebox otherword" with array[0]

This is the regex:

this.rel.match(/facebox\[?\.(\w+)\]?/)

Thanks Richard

Is your question about what the regex does or how to get the second word from "facebox otherword"? — Chris
– Chris, Commented Aug 10, 2011 at 14:21

miku · Accepted Answer · 2011-08-10 14:34:27Z

7

http://xenon.stanford.edu/~xusch/regexp/analyzer.html is a simple regex analyzer (among many others). ~~Since its not linkable~~, here is ~~just~~ a screenshot and the link:

enter image description here

edited Aug 10, 2011 at 14:34

answered Aug 10, 2011 at 14:20

miku

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3 Comments

Chris Over a year ago

There is actually a link at the bottom to "send to a friend": xenon.stanford.edu/~xusch/regexp/… . Looks like a great tool though it is strange the way it sometimes cuts up bits of text.

miku Over a year ago

@Chris, thanks, that's me and my attention span, and my expectation to see a "Link to this" somewhere in large font at the top of the site.

Chris Over a year ago

@miku: I'd given you the benefit of the doubt and assumed it was just a new feature since you first start using the site so you hadn't noticed it. ;-)

Rion Williams · Accepted Answer · 2011-08-10 14:24:59Z

5

I believe you are looking for is the split() function:

What you mentioned about turning words into an array is typically referred to as a split, so if you wanted to get "otherword" from "facebox otherword", you would do the following:

var test = "facebox otherword"
var word = test.split(' ')[1];

Working Demo

edited Aug 10, 2011 at 14:24

answered Aug 10, 2011 at 14:18

Rion Williams

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1 Comment

Richard Over a year ago

Thanks everyone, I get it now, really helpfull! I think I am going to use split in this case!

Daniel Hilgarth · Accepted Answer · 2011-08-10 14:51:34Z

3

Your regex matches:

facebox.abc
facebox[.abc
facebox[.abc]
facebox.abc]

with abc being at least one "word character" (letters, digits, and underscores).

edited Aug 10, 2011 at 14:51

answered Aug 10, 2011 at 14:19

Daniel Hilgarth

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Comments

J0HN · Accepted Answer · 2011-08-10 14:19:37Z

2

Note \.. That means that it is a dot, rather than any character. This regex cathches facebox.otherword

answered Aug 10, 2011 at 14:19

J0HN

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Gabriel Ross · Accepted Answer · 2011-08-10 14:20:06Z

1

This matches text like:

facebox[.blabla]
facebox.blabla

answered Aug 10, 2011 at 14:20

Gabriel Ross

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Comments

FishBasketGordo · Accepted Answer · 2011-08-10 14:20:43Z

0

The regex you have there won't match "facebook otherword", because of the \.. It's looking for a literal ".", so it would match the following: "facebook.otherword", "facebook[.otherword", "facebook.otherword]", or "facebook[.otherword]".

answered Aug 10, 2011 at 14:20

FishBasketGordo

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JAAulde · Accepted Answer · 2011-08-10 14:21:16Z

0

Checks that the string contained in the rel property of this

contains the text 'facebox'
followed by 0 or 1 open-square-brackets
followed by a dot
followed by 1 or more word characters
followed by 0 or 1 close-square-brackets

If matched, the 1 or more word characters will be contained in a sub-match.

answered Aug 10, 2011 at 14:21

JAAulde

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MikeM · Accepted Answer · 2011-08-10 14:22:42Z

0

/facebox\[?\.(\w+)\]?/

matches facebox literal
then optionally match [
then match .
then match any word
then optionally match ]

answered Aug 10, 2011 at 14:22

MikeM

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