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packages/template_binding/lib/src/template.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;
 
 /** Extensions to [Element]s that behave as templates. */
 class TemplateBindExtension extends NodeBindExtension {
   var _model;
   BindingDelegate _bindingDelegate;
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 }
 
 // Note: JS code tests that getElementById is present. We can't do that
 // easily, so instead check for the types known to implement it.
 bool _hasGetElementById(Node node) =>
     node is Document || node is ShadowRoot || node is SvgSvgElement;
 
 final Expando<_InstanceExtension> _instanceExtension = new Expando();
 
 final _isStagingDocument = new Expando();