code: function getAppendId(sHash){
  			var iIndex = jQuery.inArray(currentHash, hashHistory),
  				i, sHistory;
  			if (iIndex > -1) {
  				for (i = 0 ; i < iIndex + 1 ; i++) {
  					sHistory = hashHistory[i];
  					if (sHistory.slice(0, sHistory.length - 2) === sHash) {
  						return uid();
  					}
  				}
  			}
  
  			return "";
  		}
docs: This function checks if the combination of the identifier and data is unique in the current history stack.
  If yes, it returns an empty string. Otherwise it returns a unique id.
  
  @private