JS: RingBuffer

JS: Ring Buffer

var createRingBuffer = function(length){

  var start = 0, buffer = [];
  
  for (var i=0; i<length; i++)
	buffer[i] = -10;

  return {
    get  : function(key){return buffer[(start+key) % length];},
    push : function(item){
      buffer[start] = item;					// insert value at start
      start = (length + start +1) % length;	// advance start
    }
  };
};