title: How to use mixins in Nuxt.js app with nuxt-property-decortor
body: <p>I have used Nuxt.js in my latest project, and the language is TypeScript.
  Also, I'm using <code>nuxt-property-decorator</code>.
  I'm trying to understand the 'mixins' property in the following code.</p>
  <p>mixins.vue ↓</p>
  <pre><code>&lt;template&gt;
    &lt;div&gt;    
      &lt;p&gt;{{hello}}&lt;/p&gt;
    &lt;/div&gt;   
  &lt;/template&gt;
  
  &lt;script lang=&quot;ts&quot;&gt;
  import { Component ,Vue } from 'nuxt-property-decorator'
  import Mixin from &quot;~/mixins/mixin&quot;;
  @Component({
      mixins:[
          Mixin
      ]
  })
  export default class extends Vue{
      greeting:string = 'Hello'
  }
  &lt;/script&gt;
  </code></pre>
  <p>mixin.ts↓</p>
  <pre><code>import { Vue } from &quot;nuxt-property-decorator&quot;;
  export default class extends Vue {
      greeting:string = ''
      message:string = 'world'
      get hello(){
          return this.greeting + ' ' + this.message + '!'
      }
  }
  </code></pre>
  <p>I was expecting <code>&quot;Hello worlds!&quot;</code> in the output, but an error occurred:</p>
  <pre><code>Property or method &quot;hello&quot; is not defined on the instance but referenced during render. Make sure that this property is reactive, either in the data option, or for class-based components, by initializing the property.
  </code></pre>
  <p>Could anyone advise me?</p>