whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  1. TResult? messageCreation(
    1. String type,
    2. RunStepDetailsMessageCreation messageCreation
    )?,
  2. TResult? toolCalls(
    1. String type,
    2. List<RunStepDetailsToolCalls> toolCalls
    )?,
})

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(
          String type,
          @JsonKey(name: 'message_creation')
          RunStepDetailsMessageCreation messageCreation)?
      messageCreation,
  TResult? Function(
          String type,
          @JsonKey(name: 'tool_calls')
          List<RunStepDetailsToolCalls> toolCalls)?
      toolCalls,
}) {
  final _that = this;
  switch (_that) {
    case RunStepDetailsMessageCreationObject() when messageCreation != null:
      return messageCreation(_that.type, _that.messageCreation);
    case RunStepDetailsToolCallsObject() when toolCalls != null:
      return toolCalls(_that.type, _that.toolCalls);
    case _:
      return null;
  }
}