whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>(
  1. TResult? $default(
    1. XrayNetwork? rewriteNetwork,
    2. XrayAddress? rewriteAddress,
    3. int? rewritePort,
    4. XrayNetwork? network,
    5. XrayAddress? address,
    6. int? port,
    7. int? userLevel,
    8. List<DNSOutboundRuleConfig>? rules,
    9. String? nonIPQuery,
    10. List<int>? blockTypes,
    )?
)

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(
          XrayNetwork? rewriteNetwork,
          XrayAddress? rewriteAddress,
          int? rewritePort,
          XrayNetwork? network,
          XrayAddress? address,
          int? port,
          int? userLevel,
          List<DNSOutboundRuleConfig>? rules,
          String? nonIPQuery,
          List<int>? blockTypes)?
      $default,
) {
  final _that = this;
  switch (_that) {
    case _DNSOutboundConfig() when $default != null:
      return $default(
          _that.rewriteNetwork,
          _that.rewriteAddress,
          _that.rewritePort,
          _that.network,
          _that.address,
          _that.port,
          _that.userLevel,
          _that.rules,
          _that.nonIPQuery,
          _that.blockTypes);
    case _:
      return null;
  }
}