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# lodash.foreachright
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The modern build of lodash's `forEachRight` function exported as a standalone Node.js module. This utility provides right-to-left iteration over collections with optimized performance for arrays and support for early termination.
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## Package Information
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- **Package Name**: lodash.foreachright
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- **Package Type**: npm
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- **Language**: JavaScript
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- **Installation**: `npm install lodash.foreachright`
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- **Dependencies**: lodash._baseeachright, lodash._bindcallback, lodash.isarray
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## Core Imports
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```javascript
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var forEachRight = require('lodash.foreachright');
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```
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For modern environments:
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```javascript
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const forEachRight = require('lodash.foreachright');
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```
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## Basic Usage
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```javascript
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const forEachRight = require('lodash.foreachright');
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// Iterate over array from right to left
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forEachRight([1, 2, 3], function(value) {
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  console.log(value);
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});
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// => logs 3, 2, 1
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// Early termination on return false
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forEachRight(['a', 'b', 'c'], function(value, index) {
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  console.log(value);
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  if (index === 1) return false;
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});
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// => logs 'c', 'b' (stops at index 1)
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// With thisArg binding
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forEachRight([1, 2, 3], function(value) {
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  console.log(this.prefix + value);
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}, { prefix: 'Number: ' });
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// => logs 'Number: 3', 'Number: 2', 'Number: 1'
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```
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## Capabilities
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### Right-to-Left Collection Iteration
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Iterates over elements of a collection from right to left, executing a provided function for each element. The function supports arrays, objects, and strings with optimized performance for arrays.
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```javascript { .api }
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/**
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 * Iterates over elements of collection from right to left
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 * @param {Array|Object|string} collection - The collection to iterate over
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 * @param {Function} [iteratee] - The function invoked per iteration
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 * @param {*} [thisArg] - The this binding of iteratee
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 * @returns {Array|Object|string} Returns collection
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 */
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function forEachRight(collection, iteratee, thisArg);
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```
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**Parameters:**
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- `collection` (Array|Object|string): The collection to iterate over
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- `iteratee` (Function, optional): The function invoked per iteration. Called with arguments `(value, index|key, collection)`. Defaults to identity function.
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- `thisArg` (any, optional): The `this` binding of `iteratee`
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**Returns:**
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- (Array|Object|string): Returns the original `collection` unchanged
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**Behavior:**
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- **Arrays**: Iterates from highest index to 0, using optimized implementation when no `thisArg` is provided
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- **Objects**: Iterates over enumerable properties in reverse order
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- **Strings**: Iterates over characters from right to left
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- **Early Termination**: Iteration stops immediately if `iteratee` returns `false`
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- **Performance**: Uses specialized array implementation for better performance when possible
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**Usage Examples:**
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```javascript
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const forEachRight = require('lodash.foreachright');
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// Array iteration
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const numbers = [10, 20, 30];
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forEachRight(numbers, function(value, index, arr) {
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  console.log(`Index ${index}: ${value}`);
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});
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// => Index 2: 30, Index 1: 20, Index 0: 10
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// Object iteration
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const obj = { a: 1, b: 2, c: 3 };
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forEachRight(obj, function(value, key, obj) {
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  console.log(`${key}: ${value}`);
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});
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// => c: 3, b: 2, a: 1
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// String iteration
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forEachRight('abc', function(char, index) {
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  console.log(`${index}: ${char}`);
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});
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// => 2: c, 1: b, 0: a
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// Early termination
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const items = ['first', 'second', 'third'];
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forEachRight(items, function(item, index) {
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  console.log(item);
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  return index !== 1; // Stop when index is 1
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});
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// => logs 'third', 'second' (stops at index 1)
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// With context binding
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const context = { multiplier: 10 };
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forEachRight([1, 2, 3], function(value) {
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  console.log(value * this.multiplier);
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}, context);
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// => logs 30, 20, 10
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```
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### Alias: eachRight
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In the full lodash library, this function is also available under the alias `eachRight` (accessible as `_.eachRight`). However, this standalone module exports only the `forEachRight` function.
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```javascript { .api }
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// Note: In full lodash library context:
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// _.eachRight(collection, iteratee, thisArg)
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// 
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// This standalone module provides:
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// forEachRight(collection, iteratee, thisArg)
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```