8-7

class Module
  private     # The methods that follow are both private

  # This method works like attr_reader, but has a shorter name
  def readonly(*syms)
    return if syms.size == 0  # If no arguments, do nothing
    code = ""                 # Start with an empty string of code
    # Generate a string of Ruby code to define attribute reader methods.
    # Notice how the symbol is interpolated into the string of code.
    syms.each do |s|                     # For each symbol
      code << "def #{s}; @#{s}; end\n"   # The method definition
    end
    # Finally, class_eval the generated code to create instance methods.
    class_eval code
  end

  # This method works like attr_accessor, but has a shorter name.
  def readwrite(*syms)
    return if syms.size == 0
    code = ""
    syms.each do |s|
      code << "def #{s}; @#{s} end\n"
      code << "def #{s}=(value); @#{s} = value; end\n"
    end
    class_eval code
  end
end