TypeScript · Junior · Question 63 of 75

How do you write a reusable type for an event handler function?

type Handler = (event: MouseEvent) => void;

✓Correct answer: With a type alias for a function type
2Only with a class
3Function types can't be named

Explanation

The same can be written as an interface with a call signature, but a type alias is shorter for plain functions.

Further reading

TS Handbook: More on Functions ↗

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