| var baseCallback = require('../internal/baseCallback'), |
| baseWhile = require('../internal/baseWhile'); |
| |
| /** |
| * Creates a slice of `array` with elements taken from the beginning. Elements |
| * are taken until `predicate` returns falsey. The predicate is bound to |
| * `thisArg` and invoked with three arguments: (value, index, array). |
| * |
| * 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 _ |
| * @category Array |
| * @param {Array} array The array to query. |
| * @param {Function|Object|string} [predicate=_.identity] The function invoked |
| * per iteration. |
| * @param {*} [thisArg] The `this` binding of `predicate`. |
| * @returns {Array} Returns the slice of `array`. |
| * @example |
| * |
| * _.takeWhile([1, 2, 3], function(n) { |
| * return n < 3; |
| * }); |
| * // => [1, 2] |
| * |
| * var users = [ |
| * { 'user': 'barney', 'active': false }, |
| * { 'user': 'fred', 'active': false}, |
| * { 'user': 'pebbles', 'active': true } |
| * ]; |
| * |
| * // using the `_.matches` callback shorthand |
| * _.pluck(_.takeWhile(users, { 'user': 'barney', 'active': false }), 'user'); |
| * // => ['barney'] |
| * |
| * // using the `_.matchesProperty` callback shorthand |
| * _.pluck(_.takeWhile(users, 'active', false), 'user'); |
| * // => ['barney', 'fred'] |
| * |
| * // using the `_.property` callback shorthand |
| * _.pluck(_.takeWhile(users, 'active'), 'user'); |
| * // => [] |
| */ |
| function takeWhile(array, predicate, thisArg) { |
| return (array && array.length) |
| ? baseWhile(array, baseCallback(predicate, thisArg, 3)) |
| : []; |
| } |
| |
| module.exports = takeWhile; |