diff --git a/src/naturalSort.js b/src/naturalSort.js
index 94147444..e4e2523c 100644
--- a/src/naturalSort.js
+++ b/src/naturalSort.js
@@ -18,7 +18,13 @@
  */
 
 /* typescript
- * export declare function naturalSort<T extends any[]>(arr: T): T;
+ * export declare namespace naturalSort {
+ *     interface INaturalSort {
+ *         <T extends any[]>(arr: T): T;
+ *         comparator(a: any, b: any): number;
+ *     }
+ * }
+ * export declare const naturalSort: naturalSort.INaturalSort;
  */
 
 _('startWith root toStr');
@@ -27,6 +33,8 @@ exports = function(arr) {
     return arr.sort(naturalOrderComparator);
 };
 
+exports.comparator = naturalOrderComparator;
+
 // https://github.com/ChromeDevTools/devtools-frontend
 function naturalOrderComparator(a, b) {
     a = toStr(a);