react-fetch compatibility with 18-alpha releases

[chantastic]

Hey all!

Over the weekend, I was playing with react-fetch and Suspense

I was not able to use react-fetch with the latest build of 18-alpha (18.0.0-alpha-e4e8226c6-20210812 at the time). I got this error.

TypeError
react.unstable_getCacheForType is not a function

(This sandbox re-creates the error.)

I suspect that it's because of the way unstable_ prefixes are removed in candidate releases.

My fix was to use the experimental release with the same sha. And this worked.

{
  "dependencies": {
    "react": "0.0.0-experimental-e4e8226c6-20210812",
    "react-dom": "0.0.0-experimental-e4e8226c6-20210812",
    "react-fetch": "0.0.0-experimental-e4e8226c6-20210812",
    "react-scripts": "0.0.0",
    "sleep-promise": "9.1.0"
  }
}

I'm curious if the react-fetch example is something that we should be able to demo with pre-release versions of React 18. If so, is using the experimental releases the preferred method? Or is there a plan to bring react-fetch (et. al) into the same 18-alpha release scheme?

Thanks for your guidance!

[gaearon]

React Fetch depends on the experimental Cache API (#25). The Cache API is not included the in the 18 Alpha, and indeed is only available in the experimental builds (so React Fetch only works with them). This is because it's a lot more experimental than anything else. By comparison, createRoot and startTransition are almost "stable". It is not yet clear whether the Cache API will be a part of 18.0 release or if it will follow after it. For more details about the Suspense roadmap, you can look at #49.

If so, is using the experimental releases the preferred method?

Yes. I think it's OK to demo react-fetch itself since its API is already representative of how it will end up. But the way it connects to React (including the <Cache> API and invalidation via useCacheRefresh()) is likely to change, so please don't forget to mention that.

[chantastic]

Perfect explanation! Thank you for the clarity and additional links 🙏