A convoluted viscosity late initialization example

main.dart

class Viscosity {}

class Material {
  Future<Viscosity> computeViscosity() async {
    return Viscosity();
  }
}

class Goo {
  late Viscosity v;

  late Future<bool> isReady;

  Goo(Material m) {
    isReady = init(m);
  }

  Future<bool> init(Material m) async {
    v = await m.computeViscosity();
    return true;
  }
}

Future<void> main() async {
  var m = Material();
  var goo = Goo(m);
  // If you remove this line, the code breaks at runtime
  // with "Field 'v' has not been initialized".
  await goo.isReady;
  print(goo.v);
}