Use more for-of

maxBy.js

@@ -19,12 +19,11 @@ import isSymbol from './isSymbol.js'
  */
 function maxBy(array, iteratee) {
   let result
-  let index = -1
-  const length = array == null ? 0 : array.length
-
-  while (++index < length) {
+  if (array == null) {
+    return result
+  }
+  for (const value of array) {
     let computed
-    const value = array[index]
     const current = iteratee(value)
 
     if (current != null && (computed === undefined