From: Robert Klemme <bob.news@...>
Date: 2004-07-06T20:07:38+09:00
Subject: Re: Array::index and rindex operator


"Kristof Bastiaensen" <kristof@vleeuwen.org> schrieb im Newsbeitrag
news:pan.2004.07.06.10.51.04.229075@vleeuwen.org...
> Hi,
>
> On Tue, 06 Jul 2004 09:42:41 +1000, George Ogata wrote:
>
> > Sometimes though I wish that #index could take a block (i.e., return
> > the first index for which the block is true).  Unless I'm overlooking
> > something, there doesn't seem to be a method that does this.  I don't
> > know what others think of the idea, but that would probably go some
> > way towards your goal.
>
> I think that would be nice.  I would vote for it.
> You could do this with enumerator, but it is not so compact:
>
> require "enumerator"
>
> a = %w(one two three)
> a.enum_for(:each_with_index).find { |s, i| s == "two" }[1]
> => 1

Another solution:

a.inject(0) {|i,s| break i if "two" == s; idx+1}

#inject is just great!

Regards

    robert