closure-vs-object.js

function createCar() {
    var rpms = 0;

    function rev () {
        rpms++;
    }   

    return  { rev: rev 
            };  
}   

function Car() {
    this.rpms = 0;
}   

Car.prototype.rev = function () {
    this.rpms ++; 
}   

var start = new Date();
for (var i = 0; i < 10000; i++) {
    var car = createCar();
    for (j = 0; j < 10000; j++) {
        car.rev();
    }   
}   
console.log(new Date().getTime() - start.getTime());

start = new Date();
for (var i = 0; i < 10000; i++) {
    var car = new Car();
    for (j = 0; j < 10000; j++) {
        car.rev();
    }   
}   
console.log(new Date().getTime() - start.getTime());