forInRight (Lodash compatibility)

Use Object.keys and for...in loops instead

This forInRight function performs slowly due to creating key arrays, reverse iteration, and handling null or undefined.

Instead, use the faster and more modern Object.keys and for...in loops.

Iterates over all properties of an object (including inherited properties) in reverse order, calling a function for each property.

const result = forInRight(obj, iteratee);

Reference

forInRight(object, iteratee)

Iterates over all properties of the object in reverse order, calling the iteratee function. It iterates not only over the object's own properties but also over properties inherited through the prototype chain. Since it collects keys into an array and then iterates in reverse order, it's slower than normal iteration. If the iteratee function returns false, the iteration stops.

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

// Iterate over all properties in reverse order
const obj = { a: 1, b: 2 };
forInRight(obj, (value, key) => {
  console.log(key, value);
});
// Output: 'b' 2, 'a' 1

// Iterate in reverse order including inherited properties
function Parent() {
  this.inherited = 'value';
}
Parent.prototype.protoProperty = 'proto';

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

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

// Early termination based on condition
forInRight(obj, (value, key) => {
  console.log(key, value);
  return key !== 'a'; // Stop at 'a'
});
// Output: 'b' 2, 'a' 1

null or undefined is returned as is.

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

forInRight(null, iteratee); // null
forInRight(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.