when<TResult extends Object?> method

  1. @optionalTypeArgs
TResult when<TResult extends Object?>(
  1. TResult $default(
    1. String? id,
    2. String? iconUrl,
    3. String? iconTitle,
    4. String? iconDescription,
    )
)

A switch-like method, using callbacks.

As opposed to map, this offers destructuring. It is equivalent to doing:

switch (sealedClass) {
  case Subclass(:final field):
    return ...;
  case Subclass2(:final field2):
    return ...;
}

Implementation

@optionalTypeArgs
TResult when<TResult extends Object?>(
  TResult Function(
          @JsonKey(name: 'id') String? id,
          @JsonKey(name: 'url') String? iconUrl,
          @JsonKey(name: 'title') String? iconTitle,
          @JsonKey(name: 'description') String? iconDescription)
      $default,
) {
  final _that = this;
  switch (_that) {
    case _NavigationIcon():
      return $default(
          _that.id, _that.iconUrl, _that.iconTitle, _that.iconDescription);
    case _:
      throw StateError('Unexpected subclass');
  }
}