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conditionally check a string in typescript generics

Given the following generic

type WheneverPossible<T extends "boy" | "girl"> =  ...

I want to check conditionally on this generic like the following:

type WheneverPossible<T extends "boy" | "girl"> =  T === "boy" ? { numOfBalls: number } : { numOfDolls: number }

Is there a possibility to do something like this in Typescript?

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>Solution :

It is possible just use the extends keyword

type WheneverPossible<T extends "boy" | "girl"> =  T extends "boy"
  ? { numOfBalls: number }
  : { numOfDolls: number }

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