New version 4.0.3

linq.js

@@ -336,8 +336,8 @@ Enumerable.from = function (obj) {
             });
         }
 
-        // iterator object
-        if (typeof Symbol !== 'undefined' && typeof obj.next !== 'undefined') {
+        // object conforming to the iterator protocol
+        if (typeof obj.next == Types.Function) {
             return new Enumerable(function () {
                 return new IEnumerator(
                     Functions.Blank,
@@ -3081,4 +3081,4 @@ var Grouping = function (groupKey, elements) {
 };
 Grouping.prototype = new ArrayEnumerable();
 
-export default Enumerable;
+export default Enumerable;

package.json

@@ -3,7 +3,7 @@
   "author": "Mihai Ciuraru <[email protected]>",
   "description": "linq.js - LINQ for JavaScript",
   "type": "module",
-  "version": "4.0.2",
+  "version": "4.0.3",
   "license": "MIT",
   "homepage": "https://github.com/mihaifm/linq",
   "repository": {
@@ -24,4 +24,4 @@
   "main": "./linq.js",
   "exports": "./linq.js",
   "types": "./linq.d.ts"
-}
+}

test/iterator.js

@@ -1,4 +1,4 @@
-import { test, testModule, deepEqual } from './testutils.js'
+import { test, testModule, deepEqual, equal } from './testutils.js'
 import Enumerable from '../linq.js'
 
 testModule("Iterator");
@@ -54,6 +54,9 @@ test("from Iterable object", function () {
         actual.push(a[0]);
     }
     deepEqual(actual, [1, 2]);
+
+    const set = new Set([1, 2, 3])
+    equal(Enumerable.from(set).first(), 1)
 });
 
 test("from Iterator object", function () {