title: How to create own types in Nuxt Typescript?
body: <p>When I use <code>$_app</code> in Nuxt, it says <code>$_app</code> doesn't exist on <code>this</code>. I want to include <code>$_app</code> as my own type in Nuxt type. I tried this:</p>
  
  <pre><code>import Vue from "vue"
  
  interface AppMixin {
      user: any
  }
  
  declare module "vue/types/vue" {
      interface Vue {
          $_app: AppMixin
      }
  }
  </code></pre>
  
  <p>I don't know if it's correct. I don't even know where to import this code. Please help.</p>