[TypeScript] Typing a variable holding a component as value

When using TypeScript, it seems impossible to use a component as a type. For instance, it is not possible to type a store to hold a component instance like so:

import AnyComponent from "./AnyComponent"

const componentStore = writable<SvelteComponent>(null)

$componentStore = AnyComponent

The last line will give the following error:

Type ‘typeof <component>__SvelteComponent_’ is missing the following properties from type ‘SvelteComponentDev’: $set, $on, $destroy, $capture_state, and 2 more.

Maybe it is me that’s missed something about how components are typed, but I would like to be able to use that kind of pattern.

Here is a StackOverflow post I opened before writing this issue, where @dummdidumm instructed me to open this issue. I hope that’s ok.

[dummdidumm]

Hi there 😄 One thing is that we are missing some properties/methods on our internal definition of our Svelte component class. The other thing is that the typing is wrong, it should be writable<typeof SvelteComponent>, else you are refering to the instance of that component, not the class type.

[dummdidumm]

I don’t know why it works with type and not interface, but instead of typeof SvelteComponent write new (...args: any[]) => SvelteComponent