title: What do the hash marks (#) mean in Vue?
body: <p>I am a rather new Vue developer.
  Everywhere I go in our stack, I see code like this inside our components components:</p>
  <pre><code>&lt;template #item.active=&quot;{ value }&quot;&gt;
    &lt;div :aria-label=&quot;String(value)&quot; class=&quot;text-center&quot;&gt;
      &lt;v-icon v-if=&quot;value === null&quot;&gt;mdi-minus&lt;/v-icon&gt;
      &lt;v-icon v-else color=&quot;red&quot;&gt;mdi-close&lt;/v-icon&gt;
    &lt;/div&gt;
  &lt;/template&gt;
  </code></pre>
  <p>And for the life of me, I am cannot figure out what the <code>#item.active</code> (specifically the <code>#</code>) actually does. We have many hashed items. Like <code>&lt;template #item.actions-prepend=&quot;{item}&quot;&gt;</code> or <code>&lt;template #toolbar-extension&gt;</code></p>
  <p>Googling a # isn't an easy thing to do.
  And apparently I missed this specific video in my Vue tutorials!
  We use Nuxt and Vuetify, not sure if that helps!</p>