vue demo2

            
            <script  src="https://unpkg.com/vue@3/dist/vue.global.js"></script>

<div id="app">{{ nn }}</div>
 <script>
     const {createApp, ref} =Vue
     createApp({
        setup(){
            const nn= ref('woooo')
            return{
                nn
            }
        }
     }).mount('#app')

 </script>