How to provide more specific type for certain data attributes?

[vnphanquang]

Hello lovely people. I'm looking for a way to effectively do something like this...

// src/additional-svelte-typings.d.ts
declare module 'svelte/elements' {
	interface HTMLAttributes<T> {
		'data-custom'?: 'x';
	}
}
export {};

...as instructed in "Enhancing built-in DOM types" from Svelte docs. But because of this:

svelte/packages/svelte/elements.d.ts

Line 828 in f1c9edc

[key: `data-${string}`]: any;

The user-defined type gets "swallowed" when merged with svelte/elements. I can surely use non data-* attributes instead, but in some case I would prefer data-* for non-standard attributes.

Is there a way to get around this? Thanks all!

[7nik]

What is interesting is that if you define a variable with the type HTMLAttributes<any>["data-custom"], it will have the desired type. Maybe it's a bug somewhere in SLS.