code: function WebStore(storageObject, storageId, dataChanged) {
              // pre-condition
              console.assert(storageObject instanceof Storage, 'storageObject should be Storage');
              console.assert(typeof storageId === 'string', 'storageId should be string');
              if (dataChanged) {
                  console.assert(typeof dataChanged === 'function', 'dataChanged should be function');
              }
  
              /** 
               * Provides access to a list of key/value pairs, which are sometimes called items. 
               * Keys are strings. Any string (including the empty string) is a valid key. 
               * Values are similarly strings.
               * @access private
               * @member {Storage} 
               */
              this.storage = storageObject;
  
              /** 
               * The unique ID used as the key in which all record data are stored in the [storage]{@link WebStore#storage}.
               * @access private
               * @member {string} 
               */
              this.id = storageId;
  
              /** 
               * The callback that handles the data in [storage]{@link WebStore#storage} changed.
               * @access public
               * @member {WebStore~dataChangedCallback} 
               */
              this.dataChanged = dataChanged;
          }
docs: The data in the [storage]{@link WebStore#storage} is changed whenever a record is added, edited, or removed.
  The [dataChanged]{@link WebStore#dataChanged} method might be used any time this happens to refresh any component that is using the data.
  @access public
  @callback WebStore~dataChangedCallback
   
  Creates a new instance of class WebStore.
  @access public
  @constructs WebStore
  @param {Storage} storageObject - Either sessionStorage or localStorage objects.
  @param {string} storageId - The unique ID used as the key in which all record data are stored in the storageObject.
  @param {WebStore~dataChangedCallback=} dataChanged - The callback that handles the data in storage changed.