What does mean in a generic?

A constraint: T must have at least an id: string property

T inherits a class with an id field, as with class extends

T can be exactly { id: string } and nothing else

TypeScript · Middle · Question 3 of 75

What does `<T extends { id: string }>` mean in a generic?

✓Correct answer: A constraint: T must have at least an id: string property
2T inherits a class with an id field, as with class extends
3T can be exactly { id: string } and nothing else

Explanation

A constraint lets you safely access item.id inside the function while keeping the full type T in the result. You can pass any object with a suitable id and other fields. Classes and inheritance have nothing to do with it.

What does `<T extends { id: string }>` mean in a generic?

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What does <T extends { id: string }> mean in a generic?

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What does `<T extends { id: string }>` mean in a generic?