title: Access key from child component in vue
body: <p>According to <a href="https://v2.vuejs.org/v2/guide/list.html#v-for-with-a-Component" rel="nofollow noreferrer">Vue docs</a>, binding a key is required to use custom components in a v-for:</p>
  <pre><code>&lt;template v-for=&quot;(task,i) in tasks&quot;&gt;
      &lt;task-card v-bind:task=&quot;task&quot; v-bind:key=&quot;i&quot;&gt;&lt;/task-card&gt;
  &lt;/template&gt;
  </code></pre>
  <p>I would like to use that key in the child component (<code>task-card</code>), but neither using <code>this.key</code> or adding <code>key</code> as a prop (is a reserved Vue keyword) works. Is there a way of doing this without passing yet another prop with the value &quot;i&quot;? Currently working with <code>&quot;vue&quot;: &quot;^2.5.9&quot;</code>.</p>