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Comment by north | Hacker News Reader

This example doesn't cover all the cases you're showing above, but in megalith or MST you would typically have a clearer separation between the functions that change state and the async communication parts.

https://github.com/jnorth/megalith/blob/master/docs/examples...

https://github.com/mobxjs/mobx-state-tree#creating-async-pro...

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Yeah, I also like to use redux with a clear separation between actions that change state and those that don't. (For example, reducers only take actions prefixed by DATA_ or UI_, all other actions...the bulk of them really...don't have anything to do with changing state and are handled by other processes. But because of this I don't bother with action creators, so what do I know!)

A conceptual appeal of mobx to me is that this distinction seems baked in. The original mobx didn't click with me like redux did ¯\_(ツ)_/¯, but if MST gives transactional updates and support for redux dev tools (right?) could be worth trying.

Right, maybe I called out the wrong part of your example. redux-saga gives a really elegant way to describe the flow, but I feel at the expense of wrapping the async code with special helpers (call, put, fork, etc). You have to learn a few extra concepts for it to be comfortable. Async code in MST and megalith interact a bit more directly with the stores.

One thing I tried to do with megalith is mapping ideas from Redux to built-in language features as much as possible. An action object can trivially be represented as a function call for example—action name and payload is mapped to function name and arguments.

I think Mobx gets into trouble there by building off of observables—you have to litter your async code with different types of action markers to keep state consistent. MST tries to corral all those variations down into a smaller set, where the Redux ecosystem is layering ideas on top of an small initial core. Megalith and MST are starting from two completely opposite sides, but end up looking very similar somewhere in the middle :)

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