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# Lodash Reject
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Lodash Reject is a standalone module that exports the Lodash `_.reject` method for filtering collections by removing elements that pass a predicate test. It provides the opposite functionality of filter - returning elements that do NOT match the specified criteria.
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## Package Information
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- **Package Name**: lodash.reject
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- **Package Type**: npm
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- **Language**: JavaScript
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- **Installation**: `npm install lodash.reject`
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## Core Imports
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```javascript
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var reject = require('lodash.reject');
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```
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For ES6 modules:
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```javascript
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import reject from 'lodash.reject';
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```
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## Basic Usage
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```javascript
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var reject = require('lodash.reject');
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var users = [
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  { 'user': 'barney', 'age': 36, 'active': false },
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  { 'user': 'fred',   'age': 40, 'active': true }
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];
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// Remove inactive users
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var activeUsers = reject(users, function(o) { return !o.active; });
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// => [{ 'user': 'fred', 'age': 40, 'active': true }]
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// Using property shorthand - remove active users
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var inactiveUsers = reject(users, 'active');
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// => [{ 'user': 'barney', 'age': 36, 'active': false }]
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```
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## Capabilities
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### Collection Filtering
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Filters collection elements that do NOT pass the predicate test, returning a new array with elements that failed the test.
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```javascript { .api }
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/**
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 * The opposite of _.filter; this method returns the elements of collection 
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 * that predicate does NOT return truthy for.
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 * @param {Array|Object} collection - The collection to iterate over
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 * @param {Function|Object|Array|string} [predicate=_.identity] - The function invoked per iteration
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 * @returns {Array} Returns the new filtered array
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 */
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function reject(collection, predicate);
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```
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**Predicate Types:**
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- **Function**: `function(value, index|key, collection) { return boolean; }`
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- **Object**: `{ key: value }` - matches objects with specified properties
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- **Array**: `['property', value]` - matches objects where property equals value  
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- **String**: `'property'` - checks property truthiness
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**Usage Examples:**
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```javascript
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var users = [
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  { 'user': 'barney', 'age': 36, 'active': false },
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  { 'user': 'fred',   'age': 40, 'active': true },
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  { 'user': 'pebbles', 'age': 1,  'active': false }
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];
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// Function predicate - reject inactive users
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reject(users, function(o) { return !o.active; });
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// => [{ 'user': 'fred', 'age': 40, 'active': true }]
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// Object matching - reject users matching criteria
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reject(users, { 'age': 40, 'active': true });
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// => [{ 'user': 'barney', 'age': 36, 'active': false }, { 'user': 'pebbles', 'age': 1, 'active': false }]
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// Property-value pair - reject users with specific property value
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reject(users, ['active', false]);
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// => [{ 'user': 'fred', 'age': 40, 'active': true }]
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// Property name - reject users where property is truthy
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reject(users, 'active');
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// => [{ 'user': 'barney', 'age': 36, 'active': false }, { 'user': 'pebbles', 'age': 1, 'active': false }]
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// With arrays of primitive values
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reject([1, 2, 3, 4, 5], function(n) { return n % 2 === 0; });
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// => [1, 3, 5]
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// With object collections
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var inventory = {
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  'apple': { count: 5, expired: false },
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  'banana': { count: 0, expired: true },
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  'orange': { count: 3, expired: false }
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};
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reject(inventory, function(item) { return item.expired || item.count === 0; });
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// => { 'apple': { count: 5, expired: false }, 'orange': { count: 3, expired: false } }
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```