VueUse

watchOnce

watch that only triggers once.

Usage

After the callback function has been triggered once, the watch will be stopped automatically.

import { watchOnce } from '@vueuse/core'

watchOnce(source, () => {
  // triggers only once
  console.log('source changed!') 
})

Type Declarations 

export declare function watchOnce<
  T extends Readonly<WatchSource<unknown>[]>,
  Immediate extends Readonly<boolean> = false
>(
  source: T,
  cb: WatchCallback<MapSources<T>, MapOldSources<T, Immediate>>,
  options?: WatchOptions<Immediate>
): void
export declare function watchOnce<
  T extends Readonly<WatchSource<unknown>[]>,
  Immediate extends Readonly<boolean> = false
>(
  source: T,
  cb: WatchCallback<MapSources<T>, MapOldSources<T, Immediate>>,
  options?: WatchOptions<Immediate>
): void
export declare function watchOnce<
  T,
  Immediate extends Readonly<boolean> = false
>(
  sources: WatchSource<T>,
  cb: WatchCallback<T, Immediate extends true ? T | undefined : T>,
  options?: WatchOptions<Immediate>
): void

Source

Source • Docs