Vue · Middle · Question 8 of 75

Why is mutating state inside a computed getter a bug?

✓Correct answer: Computed getters must be pure; side effects make updates unpredictable and can cause infinite loops
2Computed getters run only on the server
3Mutations inside computed are silently ignored

Explanation

Vue may run the getter at any time (or not at all if nothing reads it). Use a watcher for side effects and keep computed purely derived.

Further reading

Vue: Computed Properties ↗

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