boot.js

/*
 * Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
 * This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
 * The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
 * The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
 * Code distributed by Google as part of the polymer project is also
 * subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
 */
(function(scope){

// imports
initializeModules = scope.initializeModules;

/*
NOTE: Even when native HTMLImports exists, the following api is available by
loading the polyfill. This provides api compabitility where the polyfill
cannot be "correct":

  * `document._currentScript`
  * `HTMLImportsLoaded` event
  * `HTMLImports.whenReady(callback)
*/
if (scope.useNative) {
  return;
}

// Initialize polyfill modules. Note, polyfill modules are loaded but not 
// executed; this is a convenient way to control which modules run when 
// the polyfill is required and allows the polyfill to load even when it's
// not needed.
initializeModules();

// imports
var rootDocument = scope.rootDocument;

/*
  Bootstrap the imports machine.
*/
function bootstrap() {
  HTMLImports.importer.bootDocument(rootDocument);
}
  
// TODO(sorvell): SD polyfill does *not* generate mutations for nodes added
// by the parser. For this reason, we must wait until the dom exists to 
// bootstrap.
if (document.readyState === 'complete' ||
    (document.readyState === 'interactive' && !window.attachEvent)) {
  bootstrap();
} else {
  document.addEventListener('DOMContentLoaded', bootstrap);
}

})(HTMLImports);