Properly implement implicit sharing of WeatherForecast
Make the private class inherit from QSharedData and use a QSharedDataPointer to hold the private data.
This allows the users to pass WeatherForecast instead of QExplicitlySharedDataPointer
Make the private class inherit from QSharedData and use a QSharedDataPointer to hold the private data.
This allows the users to pass WeatherForecast instead of QExplicitlySharedDataPointer