code: function removeCachedResult(removedLru) {
  	var removedLruLen = removedLru.length,
  		currentLru = removedLru[removedLruLen - 1],
  		tmp,
  		i;
  
  	currentLru.cacheItem.delete(currentLru.arg);
  
  	// walk down the tree removing dead branches (size 0) along the way
  	for (i = removedLruLen - 2; i >= 0; i--) {
  		currentLru = removedLru[i];
  		tmp = currentLru.cacheItem.get(currentLru.arg);
  
  		if (!tmp || !tmp.size) {
  			currentLru.cacheItem.delete(currentLru.arg);
  		} else {
  			break;
  		}
  	}
  }
docs: remove least recently used cache item and all dead branches