Equivalent of Writable<T> in $state

[J4gQBqqR]

Hi, I have a general question on how to initiate things in $state rune to replace store. Say the following code:

export const sections: Writable<SectionClass> = writable();

If I do it in $state rune like this:

export const sections: SectionClass = $state();

Typescript will tell me:

Type 'SectionClass | undefined' is not assignable to type 'SectionClass'.
  Type 'undefined' is not assignable to type 'SectionClass'.ts(2322)

However, I do not want to do either of the following two things:

1. initiate the SectionClass inside of the $state declaration. I do not know the exact data at the point of declaring it. I will need to init the data later in my code after my component is mounted.
2. add an "undefined" type into the SectionClass definition. This will create a lot of headache later in my code since I allow undefined in its definition.

Is there something equivalent to Writable<SectionClass> type declaration for $state rune? Can I say my variable is a $state of SectionClass without even initializing its values? If this is possible, could we add it to the documentation?

[J4gQBqqR]

Note:

export const sections = $state<SectionClass>();

Will make the type of sections being SectionClass | undefined, which is not what I want.

export const sections: Writable<SectionClass> = writable();

Will only make the type of sections being SectionClass.

[brunnerh]

You will need an assertion since $state adds undefined, e.g.

export const sections: SectionClass = $state()!;
// or
export const sections = $state<SectionClass>()!;
// or
export const sections: SectionClass = $state() as any;

[david-plugge]

export const sections = $state() as SectionClass;

Is what i use in such cases

[CrendKing]

Try const sections: SectionClass = $state({} as SectionClass);