add hw2

node_modules/lodash-es/findIndex.js

@@ -0,0 +1,55 @@
+import baseFindIndex from './_baseFindIndex.js';
+import baseIteratee from './_baseIteratee.js';
+import toInteger from './toInteger.js';
+
+/* 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);
+}
+
+export default findIndex;