private IObservableMap <I, INode, T> CreateNewInstance(IMap <string, INode> childNodes, IStateTreeNode meta) { return(ObservableMap <I, INode, T> .FromIn(childNodes.Aggregate(new Map <I, INode>(), (acc, pair) => { acc[Converter(pair.Key)] = pair.Value; return acc; }), null, this, meta)); // addHiddenFinalProp(map, "put", put) }