call_dynamically.rb

drew.send(:battle_cry)
# => Drew says zing!!!

dynamic_closure_instance_method.rb

class Object
  def metaclass
    class << self; self; end
  end
end

sword_symbol = "*********"

drew.metaclass.send(:define_method, 'swing') do |sound_effect|
  puts "#{name}: #{sword_symbol} #{sound_effect}"
end

drew.swing 'slash!!'
# => Drew: ********* slash!!

dynamic_closure_method.rb

color_name = 'black'

Ninja.send(:define_method, 'color') do
  puts "#{name}'s color is #{color_name}"
end

drew.color
# => Drew's color is black
adam.color
# => Adam's color is black

dynamic_method.js

drew['battleCry']();
// => Drew says zing!!!

instance_behavior.rb

def drew.throw_star
  puts "throwing a star"
end

drew.throw_star
# => throwing a star

instance_specific.js

drew.throwStar = function () {
  puts("throwing a star");
}

drew.throwStar();
// => throwing a star

reopen_class.rb

class Ninja
  def battle_cry
    puts "#{name} says zing!!!"
  end
end

drew.battle_cry
# => Drew says zing!!!
adam.battle_cry
# => Adam says zing!!!

reopen_prototype.js

Ninja.prototype.battleCry = function () {
  puts(this.name + " says zing!!!");
}

drew.battleCry();
// => Drew says zing!!!
adam.battleCry();
// => Adam says zing!!!

setup.js

var puts = require('sys').puts;

function Ninja(name) {
  this.name = name;
}

var drew = new Ninja("Drew");
var adam = new Ninja("Adam");

setup.rb

class Ninja
  attr_accessor :name

  def initialize(name)
    @name = name
  end
end

drew = Ninja.new("Drew")
adam = Ninja.new("Adam")