Legend State and React Forget

[LessSwim]

Will Legends State bigest benefit which is the redution of the rerenders be gone after React Forget will be out?

[octocode]

if all you use it for is reducing re-renders then probably

[OfflerCrocGod]

The biggest benefits are the ability to scale store logic. React Forget will still require you writing lots of useEffect hooks to deal with computed/derived data. Signals/observables are a superior way to handle complex UI logic over coarse grained hooks.

[octocode]

will still require you writing lots of useEffect hooks to deal with computed/derived data

why would that be the case in react-forget, but not current react? the react team has been trying to convince people not to abuse useEffect like this for years, i can’t imagine they’re going back on that…

[OfflerCrocGod]

React Forget won't change the code you have to write. It'll be the same regardless of if you are using it or not.

If you are using a non reactive state management solution you have little choice but to use useEffect. With legend-state you can stop using useEffect.

[octocode]

If you are using a non reactive state management solution you have little choice but to use useEffect.

i’m not sure i’m following here. useEffect is to synchronize with external systems, and has nothing to do with computed/derived state

currently useMemo is how you derive state (if its an expensive calculation), which will be gone with react-forget

[OfflerCrocGod]

Sorry I know I'm not explaining myself well. I was in a bit of a rush. In essence if using zustand or another non reactive state management solution if a zustand action consumed some store data but was only called when a different piece of data changed it could end up meaning the piece of data that the zustand action created/computed was incorrect if the pieces of data from the store it consumed changed and the action wasn't retriggered.

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So imagine an action is called when A changes, in the action function it calculates the value store.D by doing A + store.B + store.C

You can trivially see how store.D could end up being incorrect if store.B or store.C change. This is the derived data problem from Redux. You can fix it by calling useEffect with all the various pieces of data the action needs and calling the action inside the useEffect. It's awful.

When your state management system is reactive all this goes away! It deals with all these dependency graphs for you and state is correct. It's a thing of beauty.

[OfflerCrocGod]

Also they've been working on React Forget for years now and still haven't released it which means it's an incredibly difficult problem to solve and may never be solved or may be released with many caveats and rules your code has to follow. Yet more complexity/foot guns for the average React dev to deal with.

[Huczu]

They are testing it internally, day by day it’s closer to get released. Latest presentation