Dart: Fluent 2

main.dart

void main() {
  final auth0 = Auth0('elkdanger.eu.auth0.com', 'test');
  
  // Must wrap cascade in brackets to get return result
  // of `start`
  final result = (WebAuth(auth0)
    ..audience = 'test'
    ..orgId = 'test')
    .start();
  
  // Prints 0
  print(result);
}

class Auth0 {
  final String domain;
  final String clientId;
  
  Auth0(this.domain, this.clientId);
}

class WebAuth {
  final Auth0 auth0;
  
  String? audience;
  String? orgId;
  
  WebAuth(this.auth0);
  
  start() {
    return 0;
  }
}