text: import Vue from "./instance/index";
  import { initGlobalAPI } from "./global-api/index";
  import { isServerRendering } from "core/util/env";
  import { FunctionalRenderContext } from "core/vdom/create-functional-component";
  
  // 初始化全局API
  initGlobalAPI(Vue);
  
  Object.defineProperty(Vue.prototype, "$isServer", {
    get: isServerRendering,
  });
  
  Object.defineProperty(Vue.prototype, "$ssrContext", {
    get() {
      /* istanbul ignore next */
      return this.$vnode && this.$vnode.ssrContext;
    },
  });
  
  // expose FunctionalRenderContext for ssr runtime helper installation
  Object.defineProperty(Vue, "FunctionalRenderContext", {
    value: FunctionalRenderContext,
  });
  
  Vue.version = "__VERSION__";
  
  export default Vue;
  