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Vue 3 debugging and error handling for runtime errors, warnings, async failures, and SSR/hydration issues. Use when diagnosing or fixing Vue issues.

Use this Skill: https://skilld.dev/gh/vuejs-ai/skills/vue-debug-guides

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referenceuse-template-ref-vue35.md

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Use useTemplateRef for Template Refs in Vue 3.5+

Impact: MEDIUM - Before Vue 3.5, template refs required declaring a ref() with a name exactly matching the template's ref attribute. This fragile connection breaks silently during refactoring. Vue 3.5's useTemplateRef() eliminates this issue with explicit binding and better TypeScript support.

The legacy pattern causes no errors or warnings when names don't match - the ref simply stays null, leading to confusing debugging sessions.

Task Checklist

  • Use useTemplateRef('ref-name') in Vue 3.5+ projects
  • The first argument must exactly match the ref attribute value in the template
  • IDE support provides auto-completion for available ref names
  • TypeScript automatically infers the element type

Incorrect (Legacy Pattern):

<script setup>
import { ref, onMounted } from 'vue'

// FRAGILE: Variable name MUST match template ref value exactly
const input = ref(null)

// DANGER: After refactoring, names may not match
const inputElement = ref(null) // Renamed variable...

onMounted(() => {
  // NO ERROR - just silently null!
  inputElement.value?.focus() // Does nothing
})
</script>

<template>
  <!-- But template still uses old name -->
  <input ref="input" />
</template>
<script setup>
import { ref } from 'vue'

// TYPO: 'inupt' instead of 'input' - no warning!
const inupt = ref(null)
</script>

<template>
  <input ref="input" />
  <!-- inupt.value will always be null -->
</template>

Correct (Vue 3.5+):

<script setup>
import { useTemplateRef, onMounted } from 'vue'

// CORRECT: Explicit binding - argument matches template ref
const inputElement = useTemplateRef('my-input')

onMounted(() => {
  inputElement.value?.focus()
})
</script>

<template>
  <!-- ref name is explicitly connected via useTemplateRef argument -->
  <input ref="my-input" />
</template>
<script setup>
import { useTemplateRef, onMounted } from 'vue'

// BENEFITS:
// 1. Variable name is independent of ref attribute
// 2. IDE auto-completes available ref names
// 3. TypeScript infers correct element type
// 4. Typos in argument cause visible errors

const searchInput = useTemplateRef('search-box')
const submitButton = useTemplateRef('submit-btn')

onMounted(() => {
  // TypeScript knows these are HTMLInputElement and HTMLButtonElement
  searchInput.value?.focus()
  submitButton.value?.disabled = false
})
</script>

<template>
  <input ref="search-box" type="search" />
  <button ref="submit-btn">Submit</button>
</template>

Limitation: v-for Refs

useTemplateRef() does NOT work with v-for refs. You must use the legacy ref() pattern for collecting multiple element references in a loop.

<script setup>
import { ref, onMounted } from 'vue'

// CORRECT: Legacy pattern required for v-for refs
const itemRefs = ref([])

onMounted(() => {
  // itemRefs.value is an array of DOM elements
  itemRefs.value.forEach(el => {
    console.log(el.textContent)
  })
})
</script>

<template>
  <ul>
    <li v-for="item in items" ref="itemRefs" :key="item.id">
      {{ item.text }}
    </li>
  </ul>
</template>

Why this limitation exists: When using v-for, Vue populates the ref with an array of elements. The useTemplateRef() API was designed for single element references and does not support the array population mechanism that v-for requires.

Migration Guide

<!-- BEFORE (Vue < 3.5) -->
<script setup>
import { ref } from 'vue'
const myElement = ref(null) // Name must match template
</script>
<template>
  <div ref="myElement"></div>
</template>

<!-- AFTER (Vue 3.5+) -->
<script setup>
import { useTemplateRef } from 'vue'
const element = useTemplateRef('my-element') // Any variable name
</script>
<template>
  <div ref="my-element"></div>
</template>

Reference

Source: SKILL.md on GitHub

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  • Gen Agent Trust Hub17d

    This skill is a comprehensive collection of educational debugging guides and best practices for Vue 3 developers. It contains no executable code or malicious instructions and focuses solely on diagnosing common runtime errors and performance issues.

  • Socket17d

    No alerts

  • Snyk17d

    Risk: LOW · No issues

  • Runlayer7mo

    140/140 files flagged

  • ZeroLeaks5mo

    Score: 93/100 · 2 sections analyzed

Signed by skilld at a5fc891. This ties the file your Agent reads to that commit on GitHub. It does not review the instructions.

Last checked against GitHub 2 months ago.

Steadyupdated 8 months ago

README badge

README badge for vuejs-ai/skills/vue-debug-guides

Guides for diagnosing Vue 3 runtime errors, reactivity bugs, component lifecycle issues, and SSR hydration problems. Covers reactivity traps (refs, computed, watchers), component mechanics (props, emits, slots), templates (v-if, v-for, refs), forms (v-model), and composition API gotchas.

Generated from the current SKILL.md.

Does this cover Vue 2 or only Vue 3?
This skill is for Vue 3 only. It addresses Vue 3-specific debugging patterns like reactivity proxies, script setup, and defineEmits/defineProps.
Does this skill help with performance optimization?
No. This skill focuses on runtime errors, warnings, and behavioral bugs. For development best practices and optimization, use the separate `vue-best-practices` skill.
What kinds of issues does this cover?
Reactivity traps (refs, computed, watchers), component lifecycle bugs, template directives, form binding edge cases, SSR/hydration mismatches, slot scoping, and async-related failures.
Does this include debugging for Nuxt or other Vue frameworks?
No. This skill focuses on core Vue 3 runtime issues. Framework-specific bugs are outside its scope.

Generated from the current SKILL.md. These answers refresh after source changes.