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create-expo-cljs-app

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Create a react native application with Expo and Shadow-CLJS!

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import { useEffect, useRef } from 'react'; import { initialUpdaterRun } from '../animation'; import { BasicWorkletFunction, SharedValue } from '../commonTypes'; import { makeMutable, startMapper, stopMapper } from '../core'; import { DependencyList } from './commonTypes'; export type DerivedValue<T> = Readonly<SharedValue<T>>; export function useDerivedValue<T>( processor: BasicWorkletFunction<T>, dependencies: DependencyList ): DerivedValue<T> { const initRef = useRef<SharedValue<T> | null>(null); const inputs = Object.values(processor._closure ?? {}); // build dependencies if (dependencies === undefined) { dependencies = [...inputs, processor.__workletHash]; } else { dependencies.push(processor.__workletHash); } if (initRef.current === null) { initRef.current = makeMutable(initialUpdaterRun(processor)); } // eslint-disable-next-line @typescript-eslint/no-non-null-assertion const sharedValue: SharedValue<T> = initRef.current!; useEffect(() => { const fun = () => { 'worklet'; sharedValue.value = processor(); }; const mapperId = startMapper(fun, inputs, [sharedValue]); return () => { stopMapper(mapperId); }; }, dependencies); useEffect(() => { return () => { initRef.current = null; }; }, []); return sharedValue; }