tenebrous-dicebot/api/node_modules/lodash/findIndex.js

56 lines
1.6 KiB
JavaScript

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;