worker index basic support export/import

dist/module-debug/worker.js

@@ -1,6 +1,7 @@
 import { IndexOptions } from "./type.js";
 import { create_object, is_function, is_object, is_string } from "./common.js";
 import handler from "./worker/handler.js";
+import apply_async from "./async.js";
 
 let pid = 0;
 
@@ -90,10 +91,16 @@ register("append");
 register("search");
 register("update");
 register("remove");
+register("clear");
+register("export");
+register("import");
+
+apply_async(WorkerIndex.prototype);
 
 function register(key) {
 
-    WorkerIndex.prototype[key] = WorkerIndex.prototype[key + "Async"] = async function () {
+    WorkerIndex.prototype[key] =
+    /*WorkerIndex.prototype[key + "Async"] =*/async function () {
         const self = this,
               args = [].slice.call(arguments),
               arg = args[args.length - 1];