block_scope.rb

class Object
  def scoped(&block)
    self.instance_eval(&block)
  end
end

module Kernel
  def with_scoped(&block)
    return lambda { |obj|
      obj.instance_eval(&block)
    }
  end
end

[5, 10].each(&with_scoped do
  puts self.to_f
end)


5.scoped do
  puts self.to_f
end