NestJS · Middle · Question 12 of 75

What is `useExisting` for?

1Reusing an instance from another app
2Creating a new instance each time
✓Correct answer: Creating an alias: a second token that resolves to the same instance as an existing provider

Explanation

For example, expose a LoggerService interface token that points to an existing PinoLogger instance.

Further reading

NestJS: Custom providers ↗

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