Resettable
The Jotai core doesn't support resettable atoms.
But you can create those with helper functions from jotai/utils
.
Primitive resettable atom with atomWithReset / useResetAtom
import { useAtom } from 'jotai'import { atomWithReset, useResetAtom } from 'jotai/utils'const todoListAtom = atomWithReset([{ description: 'Add a todo', checked: false },])const TodoList = () => {const [todoList, setTodoList] = useAtom(todoListAtom)const resetTodoList = useResetAtom(todoListAtom)return (<><ul>{todoList.map((todo) => (<li>{todo.description}</li>))}</ul><buttononClick={() =>setTodoList((l) => [...l,{description: `New todo ${new Date().toDateString()}`,checked: false,},])}>Add todo</button><button onClick={resetTodoList}>Reset</button></>)}
Examples
Derived atom with RESET symbol
import { atom, useAtom, useSetAtom } from 'jotai'import { atomWithReset, useResetAtom, RESET } from 'jotai/utils'const dollarsAtom = atomWithReset(0)const centsAtom = atom((get) => get(dollarsAtom) * 100,(get, set, newValue: number | typeof RESET) =>set(dollarsAtom, newValue === RESET ? newValue : newValue / 100))const ResetExample = () => {const [dollars] = useAtom(dollarsAtom)const setCents = useSetAtom(centsAtom)const resetCents = useResetAtom(centsAtom)return (<><h3>Current balance ${dollars}</h3><button onClick={() => setCents(100)}>Set $1</button><button onClick={() => setCents(200)}>Set $2</button><button onClick={resetCents}>Reset</button></>)}