TypeScript · Middle · Question 54 of 75

What are parameter properties, and why are they not "erasable" syntax?

class User {
  constructor(private readonly name: string) {}
}

✓Correct answer: They declare and assign a field from a constructor parameter; TypeScript must generate the assignment code
2They're just type annotations
3They make parameters optional

Explanation

Since they emit JavaScript, they're rejected by erasableSyntaxOnly and by runtimes that only strip types.

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