| var baseFindIndex = require('./_baseFindIndex'), |
| baseIteratee = require('./_baseIteratee'), |
| toInteger = require('./toInteger'); |
| |
| /* Built-in method references for those with the same name as other `lodash` methods. */ |
| var nativeMax = Math.max; |
| |
| /** |
| * This method is like `_.find` except that it returns the index of the first |
| * element `predicate` returns truthy for instead of the element itself. |
| * |
| * @static |
| * @memberOf _ |
| * @since 1.1.0 |
| * @category Array |
| * @param {Array} array The array to inspect. |
| * @param {Function} [predicate=_.identity] The function invoked per iteration. |
| * @param {number} [fromIndex=0] The index to search from. |
| * @returns {number} Returns the index of the found element, else `-1`. |
| * @example |
| * |
| * var users = [ |
| * { 'user': 'barney', 'active': false }, |
| * { 'user': 'fred', 'active': false }, |
| * { 'user': 'pebbles', 'active': true } |
| * ]; |
| * |
| * _.findIndex(users, function(o) { return o.user == 'barney'; }); |
| * // => 0 |
| * |
| * // The `_.matches` iteratee shorthand. |
| * _.findIndex(users, { 'user': 'fred', 'active': false }); |
| * // => 1 |
| * |
| * // The `_.matchesProperty` iteratee shorthand. |
| * _.findIndex(users, ['active', false]); |
| * // => 0 |
| * |
| * // The `_.property` iteratee shorthand. |
| * _.findIndex(users, 'active'); |
| * // => 2 |
| */ |
| function findIndex(array, predicate, fromIndex) { |
| var length = array == null ? 0 : array.length; |
| if (!length) { |
| return -1; |
| } |
| var index = fromIndex == null ? 0 : toInteger(fromIndex); |
| if (index < 0) { |
| index = nativeMax(length + index, 0); |
| } |
| return baseFindIndex(array, baseIteratee(predicate, 3), index); |
| } |
| |
| module.exports = findIndex; |