code: function calculateStepsToHash(sCurrentHash, sToHash, bPrefix){
  			var iCurrentIndex = jQuery.inArray(sCurrentHash, hashHistory),
  				iToIndex,
  				i,
  				tempHash;
  			if (iCurrentIndex > 0) {
  				if (bPrefix) {
  					for (i = iCurrentIndex - 1; i >= 0 ; i--) {
  						tempHash = hashHistory[i];
  						if (tempHash.indexOf(sToHash) === 0 && !isVirtualHash(tempHash)) {
  							return i - iCurrentIndex;
  						}
  					}
  				} else {
  					iToIndex = jQuery.inArray(sToHash, hashHistory);
  
  					//When back to home is needed, and application is started with nonempty hash but it's nonbookmarkable
  					if ((iToIndex === -1) && sToHash.length === 0) {
  						return -1 * iCurrentIndex;
  					}
  
  					if ((iToIndex > -1) && (iToIndex < iCurrentIndex)) {
  						return iToIndex - iCurrentIndex;
  					}
  				}
  			}
  
  			return 0;
  		}
docs: This function calculates the number of steps from the sCurrentHash to sToHash. If the sCurrentHash or the sToHash is not in the history stack, it returns 0.
  
  @private