TypeScript · Junior · Question 72 of 75

How do you describe an object with a method in a type?

interface Logger {
  log(message: string): void;
  level: 'info' | 'debug';
}

✓Correct answer: Use method syntax log(message: string): void (or a function-typed property)
2Methods can only be declared in classes
3Use log: method

Explanation

Both method and property syntax work. With strictFunctionTypes, property syntax gets stricter parameter checks.

Further reading

TS Handbook: Object Types ↗

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