From: Sam Roberts <sroberts@...>
Date: 2004-03-19T03:21:16+09:00
Subject: Can I stop each's iteration, and get the results so far?

Basically, I want to break from a find_all, and get the array of
elements found so far. Is this possible?

I tried this, no luck with find_all and collect, they return nil,
instead of the array so far. Any suggestions on how to do this?

$ ruby every.rb
3
6
9
12
15
18
21
24
is 20 in every?
nil
is 21 in every?
21
all n between 100 and 200?
nil
all n as a string, up to 20
nil

--> I would like not to have gotten nil for the last two...

$ cat every.rb
class EveryN
  include Enumerable

  def initialize(n)
    @n = n
  end

  def each
    y = 0
    loop do
      y = y + @n

      yield y
    end
  end
end

every = EveryN.new(3)

every.each { |n| break if n > 25; puts n }

puts "is 20 in every?"

p every.detect { |n| break if n > 20; n == 20 }

puts "is 21 in every?"

p every.detect { |n| break if n > 21; n == 21 }

puts "all n between 100 and 200?"

p every.find_all { |n| break if n > 200; n >= 100 && n <= 200 }

puts "all n as a string, up to 20"

p every.collect { |n| break if n > 20; "n is #{n}" }
 
-- 
Sam Roberts <sroberts@certicom.com>