What does the following generic function demonstrate about TypeScript’s ‘infer in conditional return types’? type Unbox = T extends { value: infer V } ? V : never; type Result = Unbox;

Question

TypeScript Professional — Hard

What does the following generic function demonstrate about TypeScript’s ‘infer in conditional return types’? type Unbox = T extends { value: infer V } ? V : never; type Result = Unbox;

Accepted Answer

The generic function Unbox uses the 'infer' keyword to extract the type of the 'value' property from the matched shape. In this case, Result is 'number' because 'infer V' captures the type of 'value' as a number.