forEachRight (Lodash Compatibility)

Use forEachRight from es-toolkit

This forEachRight function operates slowly due to handling null or undefined, ArrayLike type processing, support for various predicate function formats, etc.

Instead, use the faster and more modern forEachRight from es-toolkit.

Iterates over elements of an array or object from right to left and executes a function for each element.

forEachRight(collection, callback);

Reference

forEachRight(collection, callback)

Iterates through each element of an array, object, or string from right to left and executes the given callback function. The iteration stops if the callback returns false.

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

// Iterate array in reverse order
forEachRight([1, 2, 3], (value, index) => {
  console.log(value, index);
});
// Output: 3 2, 2 1, 1 0

// Iterate string in reverse order
forEachRight('abc', (char, index) => {
  console.log(char, index);
});
// Output: 'c' 2, 'b' 1, 'a' 0

// Iterate object in reverse order
forEachRight({ a: 1, b: 2, c: 3 }, (value, key) => {
  console.log(value, key);
});
// Output: 3 'c', 2 'b', 1 'a'

null or undefined are returned as is.

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

forEachRight(null, value => console.log(value)); // null
forEachRight(undefined, value => console.log(value)); // undefined

The iteration stops if the callback returns false.

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

forEachRight([1, 2, 3, 4], value => {
  console.log(value);
  if (value === 2) {
    return false; // Stop iteration
  }
});
// Output: 4, 3, 2

Parameters

• collection (ArrayLike<T> | Record<any, any> | string | null | undefined): The collection to iterate over. Can be an array, object, string, or null/undefined.
• callback ((item: any, index: any, arr: any) => unknown, optional): The function to execute for each element. Returns false to stop iteration. Default is the identity function.

Returns

(ArrayLike<T> | Record<any, any> | string | null | undefined): Returns the original collection as is.