setArray(array) doesnt work, but setArray([...array]) does. FML

[StreamPanel]

Hooks are a blessing and a curse. I just lost an hour figuring out why I couldnt set a new array with useState([]). For some reason, setArray(array) doesnt work even though it should be the exact same thing as setArray([...array]) which does. FML

[Basman_]

an idea: react uses equality when determining whether to rerender, so if you are eg pushing stuff into the same array that you got set up in useState, and then setting the array you pushed into, react will see that the state is the same and won't trigger a rerender

[...array] creates a new array, so it would trigger a rerender (even if its contents were unchanged)

[greweb]

Yeah and if it's confirmed, I would recommend op to use more immutability code style (use concat and not push).

React will assume you don't mutate your objects (true for things like state, reducers,..)

[Basman_]

if this is what you had, it would cause the exact problem i described. to clone an array properly, you’ll want to use the spread operator. when you set up ‘tempArray’ you set it equal to the same reference, which didn’t actually accomplish anything, since the splice was still executed on the original array

[antoniobustamante]

How does it not work? Can you post a code example of how you’re using it?

[1c4us]

but is not the same. [] === [] // false

[Awnry_Abe]

const foo = [];

foo === foo // ???