title: How to access data from computed property Vue.js
body: <p>I'm using Vue.js and when I try to access a variable from data inside a computed property, it returns <code>undefined</code>.
  Here's the code:</p>
  
  <pre><code>    &lt;script&gt;
       export default {
         name: 'app',
         data: () =&gt; {
           return {
             lang: 'sp'
           }
         },
         computed: {
           langEn: () =&gt; this.lang === 'en',
           langSp: () =&gt; this.lang === 'sp'
         }
       }
      &lt;/script&gt;
  </code></pre>
  
  <p>This is in a NPM project. And inside a <code>.vue</code> file. Maybe it behaves differently when used like this?</p>
  
  <p>Thanks for the help</p>