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test/codegen/expect/collection/iterable_zip.js

 dart_library.library('collection/iterable_zip', null, /* Imports */[
   "dart/_runtime",
   'dart/collection',
   'dart/core'
 ], /* Lazy imports */[
 ], function(exports, dart, collection, core) {
   'use strict';
   let dartx = dart.dartx;
   const _iterables = Symbol('_iterables');
   class IterableZip extends collection.IterableBase$(core.List) {
     IterableZip(iterables) {
       this[_iterables] = iterables;
       super.IterableBase();
     }
     get iterator() {
-      let iterators = this[_iterables][dartx.map](dart.fn(x => dart.dload(x, 'iterator')))[dartx.toList]({growable: false});
+      let iterators = this[_iterables][dartx.map](dart.fn(x => x[dartx.iterator], core.Iterator, [core.Iterable]))[dartx.toList]({growable: false});
       return new _IteratorZip(iterators);
     }
   }
   dart.setSignature(IterableZip, {
     constructors: () => ({IterableZip: [IterableZip, [core.Iterable$(core.Iterable)]]})
   });
   dart.defineExtensionMembers(IterableZip, ['iterator']);
   const _iterators = Symbol('_iterators');
   const _current = Symbol('_current');
   class _IteratorZip extends core.Object {
@@ skipping 20 matching lines @@
     }
   }
   _IteratorZip[dart.implements] = () => [core.Iterator$(core.List)];
   dart.setSignature(_IteratorZip, {
     constructors: () => ({_IteratorZip: [_IteratorZip, [core.List]]}),
     methods: () => ({moveNext: [core.bool, []]})
   });
   // Exports:
   exports.IterableZip = IterableZip;
 });