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Atom.reduceByPointer() method

Reduces the value at the given pointer

Signature:

reduceByPointer<S>(pointerOrFn: Pointer<S> | ((p: Pointer<State>) => Pointer<S>), reducer: (s: S) => S): void;

Parameters

Parameter	Type	Description
pointerOrFn	[Pointer](./backstage-dataverse.pointer.md)<!-- -->&lt;S&gt; \	((p: Pointer<State>) => Pointer<S>)

const atom = atom({ a: { b: 1 } })
atom.reduceByPointer(atom.pointer.a.b, (b) => b + 1) // atom.get().a.b === 2
atom.reduceByPointer((p) => p.a.b, (b) => b + 1) // atom.get().a.b === 2

| | reducer | (s: S) => S | |

Returns:

void