docs: function next() {
  	
  		var fns = activeQueue.shift();
  
  		if ( !fns ) {
  			return;
  		}
  
  		ret = ret.then(
  			typeof fns[0] === 'function' ? fns[0].bind(self) : fns[0],
  			typeof fns[1] === 'function' ? fns[1].bind(self) : fns[1]
  		);
  
  		next();
  	}