Files
stack/packages/mosaic/framework/skills/vue-best-practices/reference/slot-name-reserved-prop.md
T
fargo 1a822493ba format: apply repo prettier (3.8.1) to the folded skills tree
963 markdown files reformatted with the repository's pinned prettier so
pnpm format:check covers the folded tree like every other repo file.

The formatter's embedded-language pass also normalized code fences
(TS semicolons, closed HTML tags in examples, lowercased CSS hex colors,
one renumbered list that skipped an index). Alphanumeric token deltas vs
the fold commit were audited file-by-file; all are formatter-equivalent
markup normalizations plus the four sanitized skills.
2026-08-19 14:37:17 -05:00

2.9 KiB

title, impact, impactDescription, type, tags
title impact impactDescription type tags
Slot Name is Reserved and Not Included in Slot Props LOW Expecting 'name' in scoped slot props when it's reserved causes confusion gotcha
vue3
slots
scoped-slots
reserved-props
naming

Slot Name is Reserved and Not Included in Slot Props

Impact: LOW - When using scoped slots, the name attribute on the <slot> element is reserved for identifying the slot. It is not passed as part of the slot props to the parent component.

Task Checklist

  • Don't expect name in slot props - it's reserved
  • Use a different prop name if you need to pass a name value
  • Remember only explicitly bound attributes become slot props

Incorrect Expectation:

<!-- ChildComponent.vue -->
<template>
  <div>
    <slot name="header" title="Welcome"></slot>
  </div>
</template>
<!-- ParentComponent.vue -->
<ChildComponent>
  <template #header="props">
    <!-- props = { title: "Welcome" } -->
    <!-- 'name' is NOT included! -->
    {{ props.name }}  <!-- undefined -->
    {{ props.title }} <!-- "Welcome" -->
  </template>
</ChildComponent>

If You Need to Pass a "Name" Value:

<!-- ChildComponent.vue -->
<template>
  <div>
    <!-- Use a different prop name like 'slotName' or 'label' -->
    <slot name="header" :label="slotLabel" :title="title"></slot>
  </div>
</template>

<script setup>
const slotLabel = 'header';
const title = 'Welcome';
</script>
<!-- ParentComponent.vue -->
<ChildComponent>
  <template #header="{ label, title }">
    <h2>{{ title }}</h2>
    <span>Section: {{ label }}</span>
  </template>
</ChildComponent>

What Gets Passed as Slot Props

Attribute on <slot> Passed to Parent?
name No (reserved for slot identification)
:text="message" Yes, as text
:count="5" Yes, as count
v-bind="object" Yes, spreads object properties
class="..." No (not bound with :)

Multiple Named Slots Example

<!-- TabPanel.vue -->
<template>
  <div class="tabs">
    <slot name="tab1" :active="activeTab === 1" :label="'First Tab'"></slot>
    <slot name="tab2" :active="activeTab === 2" :label="'Second Tab'"></slot>
  </div>
</template>

<script setup>
import { ref } from 'vue';
const activeTab = ref(1);
</script>
<!-- Usage -->
<TabPanel>
  <template #tab1="{ active, label }">
    <!-- 'name' not available, but 'label' is -->
    <button :class="{ active }">{{ label }}</button>
  </template>

  <template #tab2="{ active, label }">
    <button :class="{ active }">{{ label }}</button>
  </template>
</TabPanel>

Reference