update()

update<T>(object, path, updater): T

Updates the value at path of object using an updater function, returning a new object (immutable).

💎 Why is this a Hidden Gem?

Apply a transformation to a deeply nested value without touching the rest.

DEPRECATED

Use set(obj, path, fn(get(obj, path))) directly instead.

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Type Parameters

T: T extends object

The type of the input object.

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Parameters

object: T

The object to modify.

path: string | (string | number | symbol)[]

The path of the property to update.

updater: (value) => unknown

The function to produce the updated value.

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Returns: T

A new object with the updated value.

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See Also

• get
• set

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Since

2.0.0

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Also known as

update (Lodash, es-toolkit) · ❌ (Remeda, Radashi, Ramda, Effect, Modern Dash, Antfu)

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Example

const object = { a: { b: { c: 3 } } };

// ❌ Deprecated approach
update(object, 'a.b.c', n => n * 2);
// => { a: { b: { c: 6 } } }

// ✅ Recommended approach
set(object, 'a.b.c', get(object, 'a.b.c') * 2);
// => { a: { b: { c: 6 } } }

// Or with optional chaining for simple cases
const value = object.a?.b?.c ?? 0;
set(object, 'a.b.c', value * 2);

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How it works?

Updates value at path using updater function (immutable).

Processing Flow

Common Inputs

Object	Path	Updater	Result
{a: {b: 3}}	'a.b'	n => n * 2	{a: {b: 6}}
{count: 0}	'count'	n => n + 1	{count: 1}

Deprecated: Use set(obj, path, fn(get(obj, path))) directly.

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Use Cases

Update nested value 📌

Update value at path with function.

#update#nested#transform#immutable

import { get, set } from '@pithos/arkhe';
const updated = set(obj, 'a.b.c', get(obj, 'a.b.c') * 2);

Increment counter

Update nested counter.

#increment#counter#update#state

import { get, set } from '@pithos/arkhe';
const path = 'stats.views';
const newState = set(state, path, (get(state, path) as number) + 1);