Vuejs nested slots: how to pass slot to grandchild

If you put the slot attribute on a html element, that html element is passed to the child component to fill the slot with that name. If you don’t want to pass along a html element, you can use slot on a template tag within your component. A template tag groups elements, but does not render to a html element, which is perfect here. You can use template tags also for other things, such as to group elements in a v-if for example, or to repeat multiple elements with a v-for.

// App.vue
<template>
  <div id="app">
    <test>
      <template slot="activator">
        Click <b>me</b>!
      </template>
    </test>
  </div>
</template>

// Test.vue
<template>
  <div class="wrapper">
    <grand-child>
      <template slot="activator">
        <slot name="activator"></slot>
      </template>
    </grand-child>

    This is some text
  </div>
</template>

// GrandChild.vue
<template>
  <div>
    <a href="#" @click="toggle = !toggle">
      <slot name="activator">Default</slot>
    </a>

    <div v-if="toggle">This appears and disappears</div>
  </div>
</template>

Edit: If you want to do this for arbitrary slots, this is also possible. this.$slots contains the slots and their content, so with something like the following, you can pass the slot content to a slot with the same name:

<grand-child>
  <template v-for="(_, slot) in $slots">
    <template :slot="slot">
      <slot :name="slot"></slot>
    </template>
  </template>
</grand-child>

For completeness sake, scoped slots can be accessed through $scopedSlots and be propagated like so:

<grand-child>
  <template v-for="(_, slot) in $scopedSlots" v-slot:[slot]="props">
    <slot :name="slot" v-bind="props" />
  </template>
</grand-child>

^{source and comment}