gistfile1.js

// faster dequeue
// uses and array as prototype so all array methods are available.
// "unshift" has method overridden to not re-size the array
//
// var queue = new Queue();

function Queue() {
    this._i = 0;
}
Queue.prototype = [];
Queue.prototype.unshift = function() {
    var i = this._i;
    if(i < this.length) {
        var val = this[this._i];
        this[this._i] = null;
        this._i++;
        return val;
    }
    else {
        return null;
    }
};