iteratee.js (1700B)
1 var baseClone = require('./_baseClone'), 2 baseIteratee = require('./_baseIteratee'); 3 4 /** Used to compose bitmasks for cloning. */ 5 var CLONE_DEEP_FLAG = 1; 6 7 /** 8 * Creates a function that invokes `func` with the arguments of the created 9 * function. If `func` is a property name, the created function returns the 10 * property value for a given element. If `func` is an array or object, the 11 * created function returns `true` for elements that contain the equivalent 12 * source properties, otherwise it returns `false`. 13 * 14 * @static 15 * @since 4.0.0 16 * @memberOf _ 17 * @category Util 18 * @param {*} [func=_.identity] The value to convert to a callback. 19 * @returns {Function} Returns the callback. 20 * @example 21 * 22 * var users = [ 23 * { 'user': 'barney', 'age': 36, 'active': true }, 24 * { 'user': 'fred', 'age': 40, 'active': false } 25 * ]; 26 * 27 * // The `_.matches` iteratee shorthand. 28 * _.filter(users, _.iteratee({ 'user': 'barney', 'active': true })); 29 * // => [{ 'user': 'barney', 'age': 36, 'active': true }] 30 * 31 * // The `_.matchesProperty` iteratee shorthand. 32 * _.filter(users, _.iteratee(['user', 'fred'])); 33 * // => [{ 'user': 'fred', 'age': 40 }] 34 * 35 * // The `_.property` iteratee shorthand. 36 * _.map(users, _.iteratee('user')); 37 * // => ['barney', 'fred'] 38 * 39 * // Create custom iteratee shorthands. 40 * _.iteratee = _.wrap(_.iteratee, function(iteratee, func) { 41 * return !_.isRegExp(func) ? iteratee(func) : function(string) { 42 * return func.test(string); 43 * }; 44 * }); 45 * 46 * _.filter(['abc', 'def'], /ef/); 47 * // => ['def'] 48 */ 49 function iteratee(func) { 50 return baseIteratee(typeof func == 'function' ? func : baseClone(func, CLONE_DEEP_FLAG)); 51 } 52 53 module.exports = iteratee;