syncRefs

Keep target refs in sync with a source ref

Usage

import { syncRefs } from '@vueuse/core'
import { shallowRef } from 'vue'

const source = shallowRef('hello')
const target = shallowRef('target')

const stop = syncRefs(source, target)

console.log(target.value) // hello

source.value = 'foo'

console.log(target.value) // foo

Sync with multiple targets

You can also pass an array of refs to sync.

import { syncRefs } from '@vueuse/core'
import { shallowRef } from 'vue'

const source = shallowRef('hello')
const target1 = shallowRef('target1')
const target2 = shallowRef('target2')

const stop = syncRefs(source, [target1, target2])

console.log(target1.value) // hello
console.log(target2.value) // hello

source.value = 'foo'

console.log(target1.value) // foo
console.log(target2.value) // foo

Watch options

The options for syncRefs are similar to watch's WatchOptions but with different default values.

export interface SyncRefOptions {
  /**
   * Timing for syncing, same as watch's flush option
   *
   * @default 'sync'
   */
  flush?: WatchOptionFlush
  /**
   * Watch deeply
   *
   * @default false
   */
  deep?: boolean
  /**
   * Sync values immediately
   *
   * @default true
   */
  immediate?: boolean
}

When setting { flush: 'pre' }, the target reference will be updated at the end of the current "tick" before rendering starts.

import { syncRefs } from '@vueuse/core'
import { nextTick, shallowRef } from 'vue'

const source = shallowRef('hello')
const target = shallowRef('target')

syncRefs(source, target, { flush: 'pre' })

console.log(target.value) // hello

source.value = 'foo'

console.log(target.value) // hello <- still unchanged, because of flush 'pre'

await nextTick()

console.log(target.value) // foo <- changed!

Type Declarations

export interface SyncRefsOptions extends ConfigurableFlushSync {
  /**
   * Watch deeply
   *
   * @default false
   */
  deep?: boolean
  /**
   * Sync values immediately
   *
   * @default true
   */
  immediate?: boolean
}
/**
 * Keep target ref(s) in sync with the source ref
 *
 * @param source source ref
 * @param targets
 */
export declare function syncRefs<T>(
  source: WatchSource<T>,
  targets: Ref<T> | Ref<T>[],
  options?: SyncRefsOptions,
): WatchHandle