| var arrayFilter = require('../internal/arrayFilter'), |
| baseCallback = require('../internal/baseCallback'), |
| baseFilter = require('../internal/baseFilter'), |
| isArray = require('../lang/isArray'); |
| |
| /** |
| * Iterates over elements of `collection`, returning an array of all elements |
| * `predicate` returns truthy for. The predicate is bound to `thisArg` and |
| * invoked with three arguments: (value, index|key, collection). |
| * |
| * If a property name is provided for `predicate` the created `_.property` |
| * style callback returns the property value of the given element. |
| * |
| * If a value is also provided for `thisArg` the created `_.matchesProperty` |
| * style callback returns `true` for elements that have a matching property |
| * value, else `false`. |
| * |
| * If an object is provided for `predicate` the created `_.matches` style |
| * callback returns `true` for elements that have the properties of the given |
| * object, else `false`. |
| * |
| * @static |
| * @memberOf _ |
| * @alias select |
| * @category Collection |
| * @param {Array|Object|string} collection The collection to iterate over. |
| * @param {Function|Object|string} [predicate=_.identity] The function invoked |
| * per iteration. |
| * @param {*} [thisArg] The `this` binding of `predicate`. |
| * @returns {Array} Returns the new filtered array. |
| * @example |
| * |
| * _.filter([4, 5, 6], function(n) { |
| * return n % 2 == 0; |
| * }); |
| * // => [4, 6] |
| * |
| * var users = [ |
| * { 'user': 'barney', 'age': 36, 'active': true }, |
| * { 'user': 'fred', 'age': 40, 'active': false } |
| * ]; |
| * |
| * // using the `_.matches` callback shorthand |
| * _.pluck(_.filter(users, { 'age': 36, 'active': true }), 'user'); |
| * // => ['barney'] |
| * |
| * // using the `_.matchesProperty` callback shorthand |
| * _.pluck(_.filter(users, 'active', false), 'user'); |
| * // => ['fred'] |
| * |
| * // using the `_.property` callback shorthand |
| * _.pluck(_.filter(users, 'active'), 'user'); |
| * // => ['barney'] |
| */ |
| function filter(collection, predicate, thisArg) { |
| var func = isArray(collection) ? arrayFilter : baseFilter; |
| predicate = baseCallback(predicate, thisArg, 3); |
| return func(collection, predicate); |
| } |
| |
| module.exports = filter; |