when<TResult extends Object?> method

  1. @optionalTypeArgs
TResult when<TResult extends Object?>(
  1. TResult $default(
    1. TCPHeaderConfig? header,
    2. bool? acceptProxyProtocol
    )
)

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(TCPHeaderConfig? header, bool? acceptProxyProtocol)
      $default,
) {
  final _that = this;
  switch (_that) {
    case _TCPConfig():
      return $default(_that.header, _that.acceptProxyProtocol);
    case _:
      throw StateError('Unexpected subclass');
  }
}