# File lib/ruby2ruby.rb, line 151
  def process_block(exp)
    result = []

    exp << nil if exp.empty?
    until exp.empty? do
      code = exp.shift
      if code.nil? or code.first == :nil then
        result << "# do nothing\n"
      else
        result << process(code)
      end
    end

    result = parenthesize result.join "\n"
    result += "\n" unless result.start_with? "("

    return result
  end