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Discussion on: React with Typescript

lukeshiru profile image
LUKESHIRU

If you have a state with 30 fields (either as props of an object or as separate states), tbh the problem is elsewhere.

And when I said that not having to do a copy of the object should be enough of a reason to not do it this way, it wasn't because of performance (even if performance would be worse in normal scenarios), but more about avoiding the boilerplate every time we update the state.
I mean, the old this.setState did that copy for us, but the useState hook doesn't because it wasn't designed to be used like that.

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joaolss profile image
João Lucas Silva • Edited on

Because you avoid shooting youself on the foot and wrongly mutating the state object, you can use immer to immutability, and you can deal with more complex trabsformation in the reducer, and in last case you can write I reducer simple enough that it just contains the code that you would have to write inside setState to mutate a variable inside the object, so you dont have to write it in each setState (or useCallback just to do that) instead you can do this logic in the reducer and use the dispatch as the setState, so yes it is definitely better to use the useReducer hook and there is no benefit at all in using useState for objects

Edit: putting a example so you can see what im talking about:

const reducer = (state, action) => ({ ...state, ...action })
...
const [state,setState] = useReducer(reducer, { a: 1, b: 2})
...
setState({ a: 3 })
// new state: { a: 3, b: 2 }
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same amount of code, safer/cleaner code

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konstagap profile image
konstagap • Edited on

"Because you avoid shooting yourself on the foot and wrongly mutating the state object" - how is your example prevents that? u not dispatching anything, u basically using useReducer as a useState. Anyways, it's good if it works for you, I don't know how come it is safer/cleaner than this
const [state,setState] = useState({ a: 1, b: 2});
setState(prev =>({...prev, a:3 });
Notice how it does the same thing without writing a reducer?
BTW you using the reducer wrong. To use useReducer right, to "avoid shooting yourself on the foot" refer to docs reactjs.org/docs/hooks-reference.h... .
I know you have seen them, but maybe take a second look so you can see what I'm talking about.

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joaolss profile image
João Lucas Silva

it is safer because you dont need to remember to spread the old object everytime you need to update the state, it is cleaner because you are only spreading an object on the reducer, and you don’t have to rely on other devs doing it. “You not dispatching anything” you clearly don’t know the difference between reducer and flux paradigm, they are connected but are not the same, the documentation states: “ useReducer is usually preferable to useState when you have complex state logic that involves multiple sub-values” in verbatim, tell me where in there it shows that im wrong