This is a example about how implement Compose Technique in Javascript.

compose.js

(function(){
  // Adding compose to Function prototype
  Function.prototype.compose = function(argFn) {
    var fnToCall = this;
    return function() {
      // This line is really complex and i don't know exactly what this line do
      return fnToCall.call(this, argFn.apply(this,arguments));
    }
  }

  // Eletronic atributes and methods
  var likeEletronic = function(){
    this.voltage = '220v';
    this.power = false;
    this.switchPower = function(){
      if (this.power === true) {
        this.power = false;
        console.info('Eletronic are off now.');
      }else{
        this.power = true;
        console.info('Eletronic are on now.');
      };
    }
    return this;
  };

  // Sound Reproducer atributes and methods
  var likeSoundReproducer = function(){
    this.watts = 60;
    this.playSound = function(sound){
      console.info('Playing the sound: '+sound);
    };
    return this;
  };
  // All sound reproducer is a eletronic
  // Composing first level
  likeSoundReproducer = likeSoundReproducer.compose(likeEletronic)

  // Micro System atributes and methods
  // Not used, just example
  var likeMicroSystem = function(){
    this.cd = false;
    this.mp3 = true;
    return this;
  };

  // TV atributes and methods
  var TV = function(){
    this.pol = 42;
    this.hdmi = true;
    return this;
  };

  // Compose a TV with full resources
  // Compose second level, likeSoundReproducer is a composed object
  // This line looks me strange...
  TV = TV.compose(likeSoundReproducer);

  // Create a new TV
  var myTV = new TV();

  // Looking my TV
  console.log(myTV);

  // Call a Eletronic method
  myTV.switchPower();

  // Call a Sound Reproducer method
  myTV.playSound('guitar.mp3');
})();