whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>(
  1. TResult? $default(
    1. Name? firstName,
    2. Name? lastName,
    3. String? dateOfBirth,
    4. Gender? gender,
    )?
)

A variant of when that fallback to returning null

It is equivalent to doing:

switch (sealedClass) {
  case Subclass(:final field):
    return ...;
  case _:
    return null;
}

Implementation

@optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>(
  TResult? Function(
          @JsonKey(name: 'firstName') Name? firstName,
          @JsonKey(name: 'lastName') Name? lastName,
          @JsonKey(name: 'dateOfBirth') String? dateOfBirth,
          @JsonKey(name: 'gender', unknownEnumValue: Gender.unknown)
          Gender? gender)?
      $default,
) {
  final _that = this;
  switch (_that) {
    case _BioData() when $default != null:
      return $default(
          _that.firstName, _that.lastName, _that.dateOfBirth, _that.gender);
    case _:
      return null;
  }
}