gistfile1.rb

class Foo
  def foo; "foo" end
  def bar; "bar" end
  def baz; "baz" end
end

class Bar < Foo
  attr_accessor :plural

  def self.wrap(*methods)
    methods.each do |method|
      define_method(method) do
        plural ? "the #{super()}s" : "a #{super()}"
      end
    end
  end

  wrap :foo, :bar, :baz
end

bar = Bar.new
puts bar.foo
puts bar.baz
bar.plural = true
puts bar.bar