Dart Extension Types as Map Keys (Be Careful)

main.dart

extension type ChannelId(String value) {}
extension type StationId(String value) {}
extension type SomeNumberId(int value) {}

Map<ChannelId, String> tvChannelNames = {ChannelId('123'): 'NBC'};

void main() {
  print(tvChannelNames[StationId('123')]); // No Error!
  print(tvChannelNames[SomeNumberId(123)]); // No Error!
  print(tvChannelNames[123]); // collection_methods_unrelated_type lint rule
  print(tvChannelNames["123"]); // collection_methods_unrelated_type lint rule
}