Private and public functions in JS.

private_public.js

// taken from http://stackoverflow.com/questions/55611/javascript-private-methods

function Restaurant() {
    var myPrivateVar;

    var private_stuff = function() { // Only visible inside Restaurant()
        myPrivateVar = "I can set this here!";
    }

    this.use_restroom = function() { // use_restroom is visible to all
        private_stuff();
    }

    this.buy_food = function() { // buy_food is visible to all
        private_stuff();
    }
}