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Comment by antonkm | Hacker News Reader

Hi, it looks sweet and easy to read, but what are actual use cases? For example, how would this pair with a React app? Is this supposed to be used as a a stand alone lib?

I have not really grasped why state machines are a big deal. (If it is)

Thanks and congrats for hitting the first page!

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IMO, state machines are becoming a "big deal" because front-end developers are finally realizing that there is a name (and strict formalism) for the patterns that they've been using to manage complex UI behavior. Not only is this standardized (SCXML), it's been heavily researched for the last 30+ years and has numerous applications in many different areas of tech.

I'm working on articles for using XState in various frameworks, such as React, Vue, Angular, etc. It's already being used in production in places like vaultproject.io, tipe.io, serviceworkies.com, and more.

You can use the interpreter or create your own. An XState machine instance has a pure .transition() method that takes the current state and event, and returns the next state (+ actions, etc.). This can be used anywhere you would determine the next state of your application (or any of your app's constituent parts).

Would xstate potentially eliminate the need for redux for state management in react?

If so, how would the implementation differ from store and reducers?

I'm a Redux maintainer. You could probably use xstate instead of Redux in some cases. You could also probably use xstate as the actual implementation of your Redux reducers, too :)

I could see them being used together with something like https://github.com/Monadical-SAS/redux-time to manage animated transitions of game states or data visualizations from one step to the next.

Meh. I’m mostly a frontender today. I learned about state machines in uny 20 years ago. I wrote a sophisticated state machine in C# 15 years ago (a back end) that drove all logic for everything happening from highway to the stacks at a major shipping terminal. Assuming that frontenders are only “just discovering” anything is quite an assumption, and comes off as ignorant and condescending.

Sorry for coming off as ignorant/condescending, it was definitely not my intention.

But to be fair, I asked this question a year ago and the majority of front-end developers were unfamiliar with state machines: https://twitter.com/DavidKPiano/status/880878305502785539 I'm glad you're not, but that's not representative of the community.

A typical GUI is a state machine (though not always a finite state machine).

Much of what a typical React + Redux app does is implementing a state machine.

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