palad1nz0
palad1nz0
TTCTheo's Typesafe Cult
Created by palad1nz0 on 4/8/2023 in #questions
Rendering a list pattern
I've been running into variations of this problem concerning the need to create an entirely new data constructs when needing to map through some data to render something: imagine I have an array of items stored as state: const [items, setItems] = useState<string[]>([]); Then I would like to append a string to items, in react I would have to call setItems by creating an entirely new array since react notices that the array has changed and does the rerender again: setItems((prev) => [...prev, newItem]); items.map((item) => <SomeComponent key={item}/ >) this seems really bad for performance if there are many items in the array, is there an alternative way to do this?
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