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Type-level functions

@RiccardoOdone•Suggest a tip•

Generics are just functions (at the type level).

const shout = (str: string) => `${str}!`
const shouted = shout("yeah")
// shouted = "yeah!"

type Shout<Str extends string> = `${Str}!`
type Shouted = Shout<"yeah">
//   ^? type Shouted = "yeah!"
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