| /** |
| * Lo-Dash 2.4.1 (Custom Build) <http://lodash.com/> |
| * Build: `lodash modularize exports="node" -o ./compat/` |
| * Copyright 2012-2013 The Dojo Foundation <http://dojofoundation.org/> |
| * Based on Underscore.js 1.5.2 <http://underscorejs.org/LICENSE> |
| * Copyright 2009-2013 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors |
| * Available under MIT license <http://lodash.com/license> |
| */ |
| var baseEach = require('../internals/baseEach'), |
| createCallback = require('../functions/createCallback'), |
| isArray = require('../objects/isArray'); |
| |
| /** |
| * Iterates over elements of a collection, returning an array of all elements |
| * the callback returns truey for. The callback is bound to `thisArg` and |
| * invoked with three arguments; (value, index|key, collection). |
| * |
| * If a property name is provided for `callback` the created "_.pluck" style |
| * callback will return the property value of the given element. |
| * |
| * If an object is provided for `callback` the created "_.where" style callback |
| * will return `true` for elements that have the properties of the given object, |
| * else `false`. |
| * |
| * @static |
| * @memberOf _ |
| * @alias select |
| * @category Collections |
| * @param {Array|Object|string} collection The collection to iterate over. |
| * @param {Function|Object|string} [callback=identity] The function called |
| * per iteration. If a property name or object is provided it will be used |
| * to create a "_.pluck" or "_.where" style callback, respectively. |
| * @param {*} [thisArg] The `this` binding of `callback`. |
| * @returns {Array} Returns a new array of elements that passed the callback check. |
| * @example |
| * |
| * var evens = _.filter([1, 2, 3, 4, 5, 6], function(num) { return num % 2 == 0; }); |
| * // => [2, 4, 6] |
| * |
| * var characters = [ |
| * { 'name': 'barney', 'age': 36, 'blocked': false }, |
| * { 'name': 'fred', 'age': 40, 'blocked': true } |
| * ]; |
| * |
| * // using "_.pluck" callback shorthand |
| * _.filter(characters, 'blocked'); |
| * // => [{ 'name': 'fred', 'age': 40, 'blocked': true }] |
| * |
| * // using "_.where" callback shorthand |
| * _.filter(characters, { 'age': 36 }); |
| * // => [{ 'name': 'barney', 'age': 36, 'blocked': false }] |
| */ |
| function filter(collection, callback, thisArg) { |
| var result = []; |
| callback = createCallback(callback, thisArg, 3); |
| |
| if (isArray(collection)) { |
| var index = -1, |
| length = collection.length; |
| |
| while (++index < length) { |
| var value = collection[index]; |
| if (callback(value, index, collection)) { |
| result.push(value); |
| } |
| } |
| } else { |
| baseEach(collection, function(value, index, collection) { |
| if (callback(value, index, collection)) { |
| result.push(value); |
| } |
| }); |
| } |
| return result; |
| } |
| |
| module.exports = filter; |