Merge pull request #479 from Mithgol/detect-extracontextual-functions

also detect functions coming from other JavaScript contexts

1 files changed, 6 insertions, 1 deletions

diff --git a/lib/async.js b/lib/async.js
index c9f355f..bca33c6 100755
--- a/lib/async.js
+++ b/lib/async.js
@@ -32,6 +32,11 @@
         return toString.call(obj) === '[object Array]';
     };
 
+    var _isFunction = function (obj) {
+        return obj instanceof Function ||
+        toString.call(obj) === '[object Function]';
+    };
+
     var _each = function (arr, iterator) {
         if (arr.forEach) {
             return arr.forEach(iterator);
@@ -439,7 +444,7 @@
         });
 
         _each(keys, function (k) {
-            var task = (tasks[k] instanceof Function) ? [tasks[k]]: tasks[k];
+            var task = _isFunction(tasks[k]) ? [tasks[k]]: tasks[k];
             var taskCallback = function (err) {
                 var args = Array.prototype.slice.call(arguments, 1);
                 if (args.length <= 1) {