text: import { initMixin } from './init'
  import { stateMixin } from './state'
  import { renderMixin } from './render'
  import { eventsMixin } from './events'
  import { lifecycleMixin } from './lifecycle'
  import { warn } from '../util/index'
  
  // Vue的构造函数
  function Vue (options) {
    if (process.env.NODE_ENV !== 'production' &&
      !(this instanceof Vue)
    ) {
      warn('Vue is a constructor and should be called with the `new` keyword')
    }
    // 初始化做了什么？
    // init是哪来的
    this._init(options)
  }
  
  initMixin(Vue) // 实现init方法
  // 实现众多实例方法
  stateMixin(Vue) // $set, $delete, $watch
  eventsMixin(Vue) // $ON, $emit, $once, $off
  lifecycleMixin(Vue) // _update, $forceUpdate, $destory
  renderMixin(Vue) //$nextTick, _render
  
  export default Vue
  