diff --git a/tslib.es6.js b/tslib.es6.js
index ddd87f6..6c1739b 100644
--- a/tslib.es6.js
+++ b/tslib.es6.js
@@ -263,10 +263,19 @@ var __setModuleDefault = Object.create ? (function(o, v) {
     o["default"] = v;
 };
 
+var ownKeys = function(o) {
+    ownKeys = Object.getOwnPropertyNames || function (o) {
+        var ar = [];
+        for (var k in o) if (Object.prototype.hasOwnProperty.call(o, k)) ar[ar.length] = k;
+        return ar;
+    };
+    return ownKeys(o);
+};
+
 export function __importStar(mod) {
     if (mod && mod.__esModule) return mod;
     var result = {};
-    if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
+    if (mod != null) for (var k = ownKeys(mod), i = 0; i < k.length; i++) if (k[i] !== "default") __createBinding(result, mod, k[i]);
     __setModuleDefault(result, mod);
     return result;
 }
diff --git a/tslib.es6.mjs b/tslib.es6.mjs
index a1d9ef5..c17990a 100644
--- a/tslib.es6.mjs
+++ b/tslib.es6.mjs
@@ -263,10 +263,19 @@ var __setModuleDefault = Object.create ? (function(o, v) {
   o["default"] = v;
 };
 
+var ownKeys = function(o) {
+  ownKeys = Object.getOwnPropertyNames || function (o) {
+    var ar = [];
+    for (var k in o) if (Object.prototype.hasOwnProperty.call(o, k)) ar[ar.length] = k;
+    return ar;
+  };
+  return ownKeys(o);
+};
+
 export function __importStar(mod) {
   if (mod && mod.__esModule) return mod;
   var result = {};
-  if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
+  if (mod != null) for (var k = ownKeys(mod), i = 0; i < k.length; i++) if (k[i] !== "default") __createBinding(result, mod, k[i]);
   __setModuleDefault(result, mod);
   return result;
 }
diff --git a/tslib.js b/tslib.js
index 95beb91..332d349 100644
--- a/tslib.js
+++ b/tslib.js
@@ -312,10 +312,19 @@ var __rewriteRelativeImportExtension;
         o["default"] = v;
     };
 
+    var ownKeys = function(o) {
+        ownKeys = Object.getOwnPropertyNames || function (o) {
+            var ar = [];
+            for (var k in o) if (Object.prototype.hasOwnProperty.call(o, k)) ar[ar.length] = k;
+            return ar;
+        };
+        return ownKeys(o);
+    };
+
     __importStar = function (mod) {
         if (mod && mod.__esModule) return mod;
         var result = {};
-        if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
+        if (mod != null) for (var k = ownKeys(mod), i = 0; i < k.length; i++) if (k[i] !== "default") __createBinding(result, mod, k[i]);
         __setModuleDefault(result, mod);
         return result;
     };