From: dblack@...
Date: 2003-10-13T09:07:36+09:00
Subject: Re: Ruby idiom for all matches in a string

Hi --

On Mon, 13 Oct 2003, Gavin Sinclair wrote:

> On Monday, October 13, 2003, 8:34:41 AM, David wrote:
>
> > What's the ruby idiom for all the matches in a string.
>
> > x="ABA  ABBBA CBBA"
> > /A(B+)/.match(x)
>
> > Ultimately, I want to get [ "B", "BBB" ]
>
> > Thanks
>
>
>     /A(B+)/.match(x).captures

That won't do it; it only gets the first one.  To get them all, you
can use String#scan:

  irb(main):008:0> x
  > "ABA  ABBBA CBBA"
  irb(main):009:0> x.scan(/A(B+)/)
  => [["B"], ["BBB"]]

The reason you get an array-of-arrays (which you may have to flatten
before it's useful) is that each scan (i.e., each application of the
regex) generates a new array of captures.  (This starts to look less
cumbersome when you've got more than one capture.)  Also, #scan takes
a block, which can be handy.


David

-- 
David Alan Black
home: dblack@superlink.net
work: blackdav@shu.edu
Web:  http://pirate.shu.edu/~blackdav