A type parameter that lets you write code for different types while keeping the link between them

The any type, used to temporarily turn off checks in functions

A base class that all other types and interfaces inherit from

TypeScript · Junior · Question 16 of 75

What is a generic?

✓Correct answer: A type parameter that lets you write code for different types while keeping the link between them
2The any type, used to temporarily turn off checks in functions
3A base class that all other types and interfaces inherit from

Explanation

function first<T>(arr: T[]): T | undefined - the result type is linked to the input array's type: first([1, 2]) returns number | undefined. With any, that link is lost. Generics are used in Array<T>, Promise<T>, useState<T>.

What is a generic?

Explanation

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