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                <div id="app">




                const templates = [];
const templatesContainer = document.getElementById('app');

// We iterate through each custom templates and precompile them
for (var i = 0; i < templatesContainer.children.length; i++) {
  const template = templatesContainer.children.item(i);
    name: template.nodeName.toLowerCase(),
    renderFunction: Vue.compile(template.innerHTML),

// This component is going to have a custom render function that will check if there's a custom template
Vue.component('overridable', {
  props: ['name'],
  render(createElement) {
    const template = templates.find(x => ===;

    // We return the default content using the default slot.
    if (!template) {
      return this.$slots.default[0];
    // Using the precompiled render function
    return$parent, createElement);

Vue.component('heading', {
  props: ['title'],
  template: `
  <overridable name="heading">
      {{ title }}

new Vue({
  el: '#app',
  template: `<heading title="Hello world"></heading>`