Handling Exceptions in Flutter Non-Void Async Functions

I'm working on a Dart/Flutter project, and I have a function that performs asynchronous operations using the async/await pattern. The function is designed to fetch data and handle errors gracefully.

Here's a simplified version of the code:

Future<List<ChannelResponseModel>> getChannelList(BuildContext context) async {  List<ChannelResponseModel> channels = [];  final result = await _channelRepository.fetchChannelTimeStamp();  result.fold(    (error) {      // What should I return here to satisfy the non-void return type?    },    (timeStamp) async {      if (!isSameAsRemoteTimeStamp(timeStamp)) {        channels = await _channelRepository.fetchOngoingChannels();        state = state.copyWith(channelData: channels, dateData: timeStamp);      }      return state.listOfChannels;    },  );}

In the error callback, I'm not sure what to return to fulfill the non-void return type requirement. I want to handle errors gracefully and provide feedback to the user without breaking the function's return type.

I appreciate any guidance or suggestions. Thank you for your help!