Generics failure example with dart

generics_failure.dart

abstract class Result<T> { }

class Success<T> extends Result<T> {
  final T body;

  Success(this.body);
}

class Failure<T> extends Result<T> {
  final String cause;

  Failure(this.cause);
}


void works(Result<String> result) {
  if(result is Success<String>) {
    print("Success: ${result.body}");
  } else if (result is Failure<String>) {
    print("Failure: ${result.cause}");
  }
}

void notWorking(Result<String> result) {
  if(result is Success) {
    print("Success: ${result.body}");
  } else if (result is Failure) {
    print("Failure: ${result.cause}");
  }
}


void main() {
  works(Success("Something"));
  works(Failure("Something"));
}