anchor.diff:    /// Sets data at actual database location to provided [value].
     /// Overwrites any existing data at actual location and all child locations.
     ///
  -  /// The [value] must be a Dart [Map], [Iterable] or primitive type.
  +  /// The [value] must be a Dart basic type or the error is thrown.
     Future set(value) => handleThenable(jsObject.set(jsify(value)));
   
     /// Sets a priority for data at actual database location.
  +  ///
  +  /// The [priority] must be a [String], [num] or [null].
     Future setPriority(priority) =>
         handleThenable(jsObject.setPriority(priority));
   
  
positive.code:   ///     var event = await ref.once("value");
    ///     print(event.snapshot.val()); //prints 4
    ///
    /// The returned value from [transactionUpdate] function must be
    /// a Dart [Map], [Iterable] or primitive type.
    ///
    /// Set [applyLocally] to [false] to not see intermediate states.
    Future<Transaction> transaction(Func1 transactionUpdate,
  
negative.code: 
    /// Ensures the data for actual location is set to the specified [value]
    /// when the client is disconnected.
    ///
    /// The [value] must be a Dart basic type or the error is thrown.
    Future set(value) => handleThenable(jsObject.set(jsify(value)));
  
    /// Ensures the data for actual location is set to the specified [value]
    /// and [priority] when the client is disconnected.
    ///
    /// The [value] must be a Dart basic type or the error is thrown.
    /// The [priority] must be a [String], [num] or [null].
    Future setWithPriority(value, priority) =>
        handleThenable(jsObject.setWithPriority(jsify(value), priority));
  
    /// Writes multiple [values] at actual location when the client is disconnected.
    ///
    /// The [values] must be a Dart basic type or the error is thrown.
    Future update(values) => handleThenable(jsObject.update(jsify(values)));
  }
  
  