Declaration merging: remove function overloads?

Let's say one of the libs come with a function like this:

// library:
declare module 'example' {
    interface Animal { }
    export function sayHello(a: Animal);
}

I want to narrow down the type to just Dog. This is my module augmentation:

// app.ts
declare module 'example' {
    interface Dog extends Animal { }
    export function sayHello(a: Dog);
}

This merges the declarations to two function overloads:

sayHello(a: Dog);
sayHello(a: Animal);

I'd like to remove the generic Animal one to get stricter type checking of my code.

I couldn't find if this has been discussed before but I would find it useful quite often. Some examples would be:

• express headers (string by default, I'd use union of string literals)
• yargs args (I'd limit them to args specific to my app)

Commencez par étudier les exemples de declaration-merging et de module-augmentation dans l’issue, y compris le comportement des surcharges pour express headers et yargs args. Le travail est terminé lorsqu’il existe un moyen pris en charge de supprimer ou de restreindre la surcharge générique d’origine, avec une vérification plus stricte pour le type augmenté.