Vue3 Script Setup 代码生成：使用框架插入 Div 并用 Function 定义方法

<div id='app'></div>
<script>
  const { createApp, ref } = Vue;
  
  const app = createApp({
    setup() {
      const count = ref(0);
      
      function increment() {
        count.value++;
      }
      
      function decrement() {
        count.value--;
      }
      
      return {
        count,
        increment,
        decrement
      };
    }
  });
  
  app.mount('#app');
</script>