var Comp = Vue.extend({
  data () {
    return {
      count: 0,
      checked: false
    }
  },
  methods: {
    increament () {
      this.count ++
    }
  },
  template: `<div>
    <input @change="increament" type="checkbox" v-model="checked"/>
    <span v-text="count"></span>
  </div>`
})

new Vue({
  el: 'app',
  components: {
    comp: Comp
  },
  template: `<comp></comp>`
})