crockford on constructors

construct.js

// pseudo-classical v1

var Mammal = function(name){
  this.name = name;
  this.get_name = function(){ 
    return this.name;
  };
  this.purr = function() { 
    return "purr" 
  };
}

var myMammal = new Mammal('Icarus');

// "pseudo-classical" v2
var Mammal = function (name) {
  this.name = name;
};
Mammal.prototype.get_name = function () { 
  return this.name;
};
Mammal.prototype.says = function () { 
  return 'purr';
};

var myMammal = new Mammal('Icarus');

// functional
var mammal = function (spec) {
  var that = {};
  that.get_name = function () { 
    return spec.name;
  };
  that.says = function () { 
    return 'purr';
  };
  return that;
};

var myMammal = mammal({name: 'Herb'});