From: Matthias Georgi <matti.georgi@...>
Date: 2006-01-04T09:52:57+09:00
Subject: Re: Implicit block parameter?

It is also possible to instance_eval a passed block, like:

module Enumerable
  def map_i(&block)
    map { |i| i.instance_eval(&block) }
  end
end

heads = queues.map_i { first }

Now the block is evaled in the scope of each item, which is a little
bit confusing, as you can't call methods of the surrounding scope.

I don't like the implicit 'it', because there are already enough things
to remember in ruby's syntax.