Accurate Javascript setInterval replacement

interval.js

function Interval(func,duration){
  if(typeof func !== "function") throw new TypeError("Expected function");
  else if(typeof duration !== "number") throw new TypeError("Expected number");

  this.func = func;
  this.duration = duration;
  this.baseline = +new Date();

  (function(_this){
    _this.timer = setTimeout(function(){
      _this.run();
    },duration);
  })(this);
};
Interval.prototype.run = function(){
  this.func.call(window);
  this.baseline += this.duration;
 
  var nextTick = this.duration + this.baseline - new Date();
  if(nextTick<0) nextTick = 0;
  
  (function(_this){
    _this.timer = setTimeout(function(){
      _this.run();
    },nextTick);
  })(this);
};

Interval.prototype.stop = function(){
  clearTimeout(this.timer);
};

Something interesting...

var time = +new Date(),
  interval = new Interval(function() {
    var n = +new Date();
    console.log(n - time);
    time = n;
  },duration);