What Are the New Features of Typescript 5?

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1. Const type parameters

Typescript will generally infer an object into a more generic type. For example, in the following example, the inferred names are string[]

type HasNames = { names: readonly string[] };
function getNamesExactly<T extends HasNames>(arg: T): T["names"] {
    return arg.names;
}

const names = getNamesExactly({ names: ["Alice"…