From: Kevin Ballard <kballard@...>
Date: 2005-10-19T00:36:58+09:00
Subject: Re: Unit testing an each function


Peter Hickman wrote:
> Sort of like this (trivial example)
>
> data = Array.new
> data << (1..5)
> data << (10..20)
>
> data.each{|i| puts i}
>
> 1..5
> 10..20
>
> # What I want to work is
>
> data.each.each{|i| puts i}
>
> 1
> 2
> 3
> 4
> 5
> 10
> 11
> 12
> 13
> 14
> 15
> 16
> 17
> 18
> 19
> 20
>
> # What I have to write is
>
> data.each{|i| i.each{|j| puts j}}
>
> No great hardship I know but I actually expected data.each.each{...} to
> work.

Huh, that's an interesting idea. Lets see if we can get it to work.

class EachProxy < Object
  instance_methods.each { |meth| undef_method(meth) unless meth.to_s =~
/^__/ }

  def initialize(obj)
    @obj = obj
  end

  def method_missing(meth, *args, &block)
    @obj.each { |item| item.send meth, *args, &block }
  end
end

class Array
  alias :__each__ :each
  def each(&blk)
    if blk
      __each__(&blk)
    else
      EachProxy.new(self)
    end
  end
end

Now your example works fine.