useStore

Vue composable for subscribing to TanStack Store state

Reference

useStore

function useStore<TState, TSelected = NoInfer<TState>>(
  store: Atom<TState> | ReadonlyAtom<TState>,
  selector?: (state: NoInfer<TState>) => TSelected,
  options?: UseStoreOptions<TSelected>
): Readonly<Ref<TSelected>>

A Vue composable that subscribes to a TanStack Store atom and returns a readonly ref. The ref will update when the selected state changes according to the equality function.

store · Atom<TState> | ReadonlyAtom<TState>

The store atom to subscribe to.

selector · (state: TState) => TSelected · default: "(d) => d"

Optional function that selects a slice of state from the atom. Defaults to returning the entire state.

options · UseStoreOptions<TSelected>

Optional configuration object.

Show properties

equal · (a: TSelected, b: TSelected) => boolean · default: "shallow"

Equality function to determine if the selected state has changed. Defaults to shallow comparison.

Returns

Readonly<Ref<TSelected>> · Readonly<Ref<TSelected>>

A readonly Vue ref containing the selected state value.

Usage

Basic Usage

<script setup>
import { useStore } from '@tanstack/vue-store'
import { store } from './store'

const count = useStore(store, (state) => state.count)
</script>

<template>
  <div>Count: {{ count }}</div>
</template>

Selecting Multiple Values

<script setup>
import { useStore } from '@tanstack/vue-store'
import { store } from './store'

const user = useStore(store, (state) => ({
  name: state.user.name,
  email: state.user.email,
  role: state.user.role
}))
</script>

<template>
  <div>
    <h2>{{ user.name }}</h2>
    <p>{{ user.email }}</p>
    <span>{{ user.role }}</span>
  </div>
</template>

Custom Equality Function

<script setup>
import { useStore } from '@tanstack/vue-store'
import { store } from './store'

// Custom deep comparison
const deepEqual = (a, b) => JSON.stringify(a) === JSON.stringify(b)

const settings = useStore(
  store,
  (state) => state.settings,
  { equal: deepEqual }
)
</script>

<template>
  <div>{{ settings }}</div>
</template>

Using Entire State

<script setup>
import { useStore } from '@tanstack/vue-store'
import { store } from './store'

// No selector - returns entire state
const state = useStore(store)
</script>

<template>
  <div>
    <p>Count: {{ state.count }}</p>
    <p>Name: {{ state.name }}</p>
  </div>
</template>

With Computed Properties

<script setup>
import { computed } from 'vue'
import { useStore } from '@tanstack/vue-store'
import { store } from './store'

const todos = useStore(store, (state) => state.todos)
const completedCount = computed(() => 
  todos.value.filter(t => t.completed).length
)
</script>

<template>
  <div>
    <p>Total: {{ todos.length }}</p>
    <p>Completed: {{ completedCount }}</p>
  </div>
</template>

Notes

• Returns a readonly ref - the value cannot be mutated directly
• Uses Vue’s watch API to track store subscriptions
• Automatically cleans up subscriptions when the component is unmounted
• Defaults to shallow equality comparison to optimize reactivity
• Uses toRaw to unwrap Vue proxies before comparison
• Compatible with both Vue 2 (via vue-demi) and Vue 3