why reduce is static?

[mehdok]

Hi Vadim

First I have to thank you for your great article.

I'm wondering is there any specific reason that you used static function for reduce or feedbacks (whenLoading, userInput)?

[lordzsolt]

While I'm not the author of the article, I can at least partly answer your questions 🙂

They are static, because you should never need to access self inside them.

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In case of reduce, it's also in the article:

Some of the states have associated values in order to draw them on the UI or to pass to the next state. Similarly, events carry data, which is the only source of information when we produce a new state inside a reduce() function.

In essence, the associated values of State and Event must be enough for you to determine the next state.

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In case of feedbacks, either the State should be enough, or dependencies should be passed in as parameters.

However, the author conveniently hardcoded MoviesAPI inside the feedbacks and basically threw any notion of testability straight out the window...
Instead, that dependency must be injected.

The only question is, should it come with the State or should it be a parameter to the feedback function (ex: static func whenLoading(moviesApi: MoviesApi) -> Feedback<State, Event>).
I'm leaning more towards the 2nd approach of passing it as a parameter to the function.

[JonnyBeeGod]

While I'm not the author of the article, I can at least partly answer your questions 🙂

They are static, because you should never need to access self inside them.

In case of reduce, it's also in the article:

Some of the states have associated values in order to draw them on the UI or to pass to the next state. Similarly, events carry data, which is the only source of information when we produce a new state inside a reduce() function.

In essence, the associated values of State and Event must be enough for you to determine the next state.

In case of feedbacks, either the State should be enough, or dependencies should be passed in as parameters.

However, the author conveniently hardcoded MoviesAPI inside the feedbacks and basically threw any notion of testability straight out the window...
Instead, that dependency must be injected.

The only question is, should it come with the State or should it be a parameter to the feedback function (ex: static func whenLoading(moviesApi: MoviesApi) -> Feedback<State, Event>).
I'm leaning more towards the 2nd approach of passing it as a parameter to the function.

Makes sense. I am wondering whether you have figured out a way of making conditional presentation of modal views work with this approach. Since this would require to somehow set a Binding in the View based on the state of the viewModel and this does not work in the body func. Subscribing to state in init also does not work since this is an escaping func. Just wondering