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packages/template_binding/lib/src/instance_binding_map.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of template_binding;
 
 class _InstanceBindingMap {
   final List bindings;
   List<_InstanceBindingMap> children;
   DocumentFragment content;
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   if (delegate == null) delegate = BindingDelegate._DEFAULT;
 
   if (delegate._bindingMaps == null) delegate._bindingMaps = new Expando();
   var map = delegate._bindingMaps[content];
   if (map == null) {
     map = _createInstanceBindingMap(content, delegate);
     delegate._bindingMaps[content] = map;
   }
   return map;
 }