<@U33H6SB2B> How to create `RequestInit` object fr...

# javascript

[Robert Jaros]

@turansky How to create RequestInit object from kotlin-wrappers in common or wasmjs code? The invoke() is only available (generated somehow?) in the js source set.

[turansky]

Workaround for now

[Robert Jaros]

So I need to declare my own external type with `var`s ?

[Robert Jaros]

I'll probably wait until it's fixed ...

[Robert Jaros]

I wonder why do you declare all these external types with `val`s and not with `var`s in the first place. It's an unnecessary limitation in my opinion.

[Robert Jaros]

In my lib I provide a function which allows user to customize the request with an optional parameter requestFilter: (suspend RequestInit.() -> Unit)? = null. RequestInit from stdlib has `var`s, so the user can modify the provided request parameters. With `val`s it can't be done so easy.

[turansky]

It doesn't work in common case, when you want more specific type for property in child interface

[Robert Jaros]

It's still a limitation. With var you can do the same as with val and more. And the JS objects are mutable anyway, so why not use mutable Kotlin values?

[turansky]

For builder, which you want, you can create mutable child. But copy is more kotlinish solution for this case.

[turansky]

In common case we want same logic as for data classes - immutable by default with copy method for transformation.

[turansky]

Single problem for now - missed js-plain-objects plugin support for WasmJS.
cc @Artem Kobzar

[turansky]

And the JS objects are mutable anyway

No.
It can be frozen 🧌
With Object.freeze or new JSON.parseImmutable
https://github.com/tc39/proposal-json-parseimmutable

[turansky]

AFAIK React props are frozen inside component for example😜

[Robert Jaros]

Ok, got the point 🙂