Izmjenjena struktura, dodan backand

web/node_modules/core-js/modules/$.iter-detect.js

@@ -0,0 +1,21 @@
+var ITERATOR     = require('./$.wks')('iterator')
+  , SAFE_CLOSING = false;
+
+try {
+  var riter = [7][ITERATOR]();
+  riter['return'] = function(){ SAFE_CLOSING = true; };
+  Array.from(riter, function(){ throw 2; });
+} catch(e){ /* empty */ }
+
+module.exports = function(exec, skipClosing){
+  if(!skipClosing && !SAFE_CLOSING)return false;
+  var safe = false;
+  try {
+    var arr  = [7]
+      , iter = arr[ITERATOR]();
+    iter.next = function(){ return {done: safe = true}; };
+    arr[ITERATOR] = function(){ return iter; };
+    exec(arr);
+  } catch(e){ /* empty */ }
+  return safe;
+};