how it works viewmodel{observe,failure}

> moviesViewModel = viewModel(viewModelFactory) {
> observe(movies, ::renderMoviesList)
> failure(failure, ::handleFailure)
> }

Taking this example, this viewmodel moves to the method _renderMoviesList_ on success and _handleFailure_ on failure.

But how is this defined in generic type, about the method and params it shall be moving towards?