From: Bill Clagett <bill@32768.com>
Date: 2004-03-19T04:20:34+09:00
Subject: Re: Can I stop each's iteration, and get the results so far?

On Fri, Mar 19, 2004 at 03:21:16AM +0900, Sam Roberts wrote:
> Basically, I want to break from a find_all, and get the array of
> elements found so far. Is this possible?
> 
...

I can't think of a way to use 'break' here. But you could use
throw and catch.

my_enumerable = (1..1000)

my_enumerable.instance_eval do
  @old_each = self.method(:each)
  def each
    catch :stop_each do
      @old_each.call {|n| yield n}
    end
  end
end

my_enumerable.collect do |n| 
  throw :stop_each if n > 20
  "n is #{n}"
end

#bill