text: // 从 Vue 实例开始看
  
  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'
  
  function Vue (options) {
    if (process.env.NODE_ENV !== 'production' &&
      !(this instanceof Vue)
    ) { // 严谨点：Vue 是一个构造函数，不能直接调用，直接调用会报错
      warn('Vue is a constructor and should be called with the `new` keyword')
    }
    this._init(options) // new Vue 时候传进来的参数，所有的选项：data, methods, computed, props, created, beforeCreate
  }
  
  initMixin(Vue) // 完毕
  stateMixin(Vue) // 完毕
  eventsMixin(Vue) // 完毕
  lifecycleMixin(Vue) // 完毕
  renderMixin(Vue)
  
  export default Vue
  