Apply let/const transform.

_baseAt.js

@@ -9,10 +9,10 @@ import get from './get.js';
  * @returns {Array} Returns the picked elements.
  */
 function baseAt(object, paths) {
-  var index = -1,
-      length = paths.length,
-      result = Array(length),
-      skip = object == null;
+  let index = -1;
+  const length = paths.length;
+  const result = Array(length);
+  const skip = object == null;
 
   while (++index < length) {
     result[index] = skip ? undefined : get(object, paths[index]);