anchor.diff:      final dynamic keys = value.keys;
       var keysValid = true;
       for (final dynamic element in keys) {
  -      if (element is! int && element is! String) {
  +      final elementType = element.runtimeType;
  +      if ((elementType is! int) && (elementType is! String)) {
           keysValid = false;
           break;
         }
  
positive.code:     var ok = true;
      for (final dynamic element in value) {
        var valType = element.runtimeType;
        if (element is List && element is! Uint8List) {
          valType = List;
        }
        if (element is Map) {
          valType = Map;
        }
        switch (valType) {
  
negative.code:     var ok = true;
      value.forEach((key, val) {
        // Encode the key, can now only be ints or strings.
        final keyType = key.runtimeType;
        if (keyType is int) {
          _writeInt(key);
        } else {
          _writeString(key);
        }
        // Encode the value
        var valType = val.runtimeType;
        if ((valType is List) && (valType is! Uint8List)) {
          valType = List;
        }
        if (valType is Map) {
          valType = Map;
        }
        switch (valType) {
  