merge method
Implementation
String? merge(final data, [final Object? data2]) {
if (this == null) {
return null;
}
if (data2 != null && data is String?) {
return this!.expand({if (data != null) data.toString(): data2});
} else if (data is Map<String, Object>) {
return this!.expand(data);
} else {
return illegalArg("Must provide a key/value pair or a map");
}
}