kopia lustrzana https://github.com/Tldraw/Tldraw
41 wiersze
1.1 KiB
TypeScript
41 wiersze
1.1 KiB
TypeScript
import { useState } from 'react'
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import { Atom, AtomOptions, atom } from '../core'
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/**
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* Creates a new atom and returns it. The atom will be created only once.
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*
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* See [[atom]]
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*
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* @example
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* ```ts
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* const Counter = track(function Counter () {
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* const count = useAtom('count', 0)
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* const increment = useCallback(() => count.set(count.value + 1), [count])
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* return <button onClick={increment}>{count.value}</button>
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* })
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* ```
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*
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* @public
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*/
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export function useAtom<Value, Diff = unknown>(
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/**
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* The name of the atom. This does not need to be globally unique. It is used for debugging and performance profiling.
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*/
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name: string,
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/**
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* The initial value of the atom. If this is a function, it will be called to get the initial value.
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*/
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valueOrInitialiser: Value | (() => Value),
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/**
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* Options for the atom.
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*/
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options?: AtomOptions<Value, Diff>
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): Atom<Value, Diff> {
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return useState(() => {
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const initialValue =
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typeof valueOrInitialiser === 'function' ? (valueOrInitialiser as any)() : valueOrInitialiser
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return atom(`useAtom(${name})`, initialValue, options)
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})[0]
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}
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