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HTML 

              
                <main x-data="TodoMVC()" x-init="init()">
  <section class="todoapp">
    <header class="header">
      <h1>todos</h1>
      <input
        type="text"
        class="new-todo"
        placeholder="What needs to be done?"
        autofocus
        x-ref="newTodoInput"
        x-model="newTodo"
        @keydown.enter="add(); save()"
        @keydown.escape="newTodo = ''"
      />
    </header>
    <!-- This section should be hidden by default and shown when there are todos -->
    <section class="main" x-show="todos.length > 0">
      <input
        type="checkbox"
        id="toggle-all"
        class="toggle-all"
        :checked="countIncomplete() === 0"
        @change="toggleAll($event); save()"
      />
      <label for="toggle-all">Mark all as complete</label>
      <ul class="todo-list">
        <!-- These are here just to show structure of the list items -->
        <!-- List items should get the class `editing` when editing and `completed` when marked as completed -->
        <template x-for="todo in listTodos()" :key="todo.id">
          <li
            :class="{ completed: todo.completed, editing: todo.editing }"
            @dblclick="editing(todo)"
          >
            <div class="view">
              <input
                type="checkbox"
                :id="`check-${todo.id}`"
                class="toggle"
                x-model="todo.completed"
                @change="toggle(todo, $event); save()"
              />
              <label x-text="todo.title"></label>
              <button class="destroy" @click="remove(todo); save()"></button>
            </div>
            <input
              type="text"
              class="edit"
              :id="`edit-${todo.id}`"
              x-model="todo.edit"
              @keydown.enter="edit(todo); save()"
              @keydown.escape="reset(todo)"
              @click.away="edit(todo); save()"
            />
          </li>
        </template>
      </ul>
    </section>
    <!-- This footer should hidden by default and shown when there are todos -->
    <footer class="footer" x-show="todos.length > 0">
      <!-- This should be `0 items left` by default -->
      <span class="todo-count" x-html="showCounter()"
        ><strong>0</strong> items left</span
      >
      <!-- Remove this if you don't implement routing -->
      <ul class="filters">
        <template x-for="item in nav">
          <li>
            <a
              :href="`#/${item.name}`"
              :class="{ selected: item.name === filter }"
              x-text="item.title"
            ></a>
          </li>
        </template>
      </ul>
      <!-- Hidden if no completed items are left ↓ -->
      <button
        class="clear-completed"
        x-show="countIncomplete() < todos.length"
        @click="clear(); save()"
      >
        Clear completed
      </button>
    </footer>
  </section>
  <footer class="info">
    <p>Double-click to edit a todo</p>
    <!-- Change this out with your name and url ↓ -->
    <p>Created by <a href="https://github.com/tlgreg">TLGreg</a></p>
    <p>Part of <a href="http://todomvc.com">TodoMVC</a></p>
  </footer>
</main>
!

CSS
!

JS 

              
                function TodoMVC() {
  const storage = Storage()
  const { todos } = storage.get()

  return {
    init() {
      // needed because #/ navigation breaks [autofocus]
      this.$refs.newTodoInput.focus()

      const router = Router({
        '/all': () => {
          this.filter = 'all'
        },
        '/active': () => {
          this.filter = 'active'
        },
        '/completed': () => {
          this.filter = 'completed'
        },
      })

      router.init('/all')
    },

    save() {
      this.$nextTick(() => {
        storage.set({ todos: this.todos })
      })
    },

    // data

    todos,
    newTodo: '',
    filter: 'all',
    nav: [
      { name: 'all', title: 'All' },
      { name: 'active', title: 'Active' },
      { name: 'completed', title: 'Completed' },
    ],

    // filtering

    listTodos() {
      switch (this.filter) {
        case 'active':
          return this.todos.filter(isNotCompleted)
        case 'completed':
          return this.todos.filter(isCompleted)
        default:
          return this.todos
      }
    },

    // toggle compeleted check

    toggleAll({ target: { checked } }) {
      this.todos.forEach(todo => {
        todo.completed = checked
      })
    },

    toggle(todo, { target: { checked } }) {
      todo.completed = checked
    },

    countIncomplete() {
      return this.todos.reduce(
        (acc, { completed }) => acc + Number(!completed),
        0,
      )
    },

    // adding new todos

    add() {
      const id = new Date().getTime()
      this.todos = [
        ...this.todos,
        { id, title: this.newTodo.trim(), completed: false },
      ]
      this.newTodo = ''
    },

    // removing todos

    remove(todo) {
      const idx = findIdx(todo, this.todos)
      this.todos = [
        ...this.todos.slice(0, idx),
        ...this.todos.slice(idx + 1, this.todos.length),
      ]
    },

    clear() {
      this.todos = this.todos.filter(isNotCompleted)
    },

    // editing todos

    editing(todo) {
      todo.editing = true
      todo.edit = todo.title

      this.$nextTick(() => {
        document.getElementById(`edit-${todo.id}`).focus()
      })
    },

    edit(todo) {
      const newTitle = todo.edit.trim()
      if (!newTitle) {
        this.remove(todo)
      } else {
        todo.title = newTitle
        this.reset(todo)
      }
    },

    reset(todo) {
      todo.editing = false
      todo.edit = ''
    },

    // counter at the bottom

    showCounter() {
      const count = this.countIncomplete()
      return `<strong>${count}</strong> item${count === 1 ? '' : 's'} left`
    },
  }
}

function Storage() {
  const KEY = 'todos-alpinejs'
  const defaultData = '{ "todos": [] }'

  return {
    get() {
      return JSON.parse(localStorage.getItem(KEY) || defaultData)
    },
    set({ todos, ...rest }) {
      localStorage.setItem(
        KEY,
        JSON.stringify({
          ...rest,
          todos: todos.map(({ id, title, completed }) => ({
            id,
            title,
            completed,
          })),
        }),
      )
    },
  }
}

function findIdx(todo, todos) {
  const idx = todos.findIndex(({ id }) => id === todo.id)
  if (idx < 0) throw Error(`Can not find todo`)
  return idx
}

function isCompleted({ completed }) {
  return completed
}

function isNotCompleted({ completed }) {
  return !completed
}
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Console