toJson method

Object? toJson(Object? callback(T? value))

Implementation

Object? toJson(Object? Function(T? value) callback) {
  if (_secondary == null) return callback(primary);
  final entries = {
    "primary": callback(primary),
    "secondary": callback(_secondary),
  }.entries.where((e) => e.value != null);
  if (entries.isEmpty) return null;
  return Map.fromEntries(entries);
}