Vue · Middle · Question 55 of 75

What does `{ once: true }` do on a watcher (Vue 3.4+)?

✓Correct answer: The callback runs only on the first change, then the watcher stops
2The callback runs immediately once
3The watcher is shared between component instances

Explanation

It replaces manually calling the stop handle inside the callback.

Further reading

Vue: Watchers ↗

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