forOwn (Lodash compatibility)

::: warning Use Object.keys with a loop instead

This forOwn function operates slowly due to internally calling the keys function, object conversion processes, and handling of null or undefined.

Instead, use the faster and more modern Object.keys with a loop.

:::

Iterates over only the object's own properties, calling a function for each property.

const result = forOwn(obj, iteratee);

Usage

forOwn(object, iteratee)

Iterates over only the object's own properties, calling the iteratee function. It iterates only over properties directly owned by the object, excluding inherited properties and Symbol keys. If the iteratee function returns false, iteration stops.

import { forOwn } from 'es-toolkit/compat';

// Iterate over only own properties of the object
const obj = { a: 1, b: 2 };
forOwn(obj, (value, key) => {
  console.log(key, value);
});
// Output: 'a' 1, 'b' 2

// Exclude inherited properties
function Parent() {
  this.inherited = 'value';
}
Parent.prototype.protoProperty = 'proto';

const child = new Parent();
child.own = 'ownValue';

forOwn(child, (value, key) => {
  console.log(key, value);
});
// Output: 'inherited' 'value', 'own' 'ownValue' (protoProperty is excluded)

// Early termination based on condition
forOwn(obj, (value, key) => {
  console.log(key, value);
  return key !== 'a'; // Stop after 'a'
});
// Output: 'a' 1

Returns null or undefined as is.

import { forOwn } from 'es-toolkit/compat';

forOwn(null, iteratee); // null
forOwn(undefined, iteratee); // undefined

Parameters

• object (T | null | undefined): The object to iterate over.
• iteratee ((value: T[keyof T], key: string, collection: T) => any, optional): The function to call for each property. Defaults to the identity function.

Returns

(T | null | undefined): Returns the original object.