Sveltekit demo - why is locals.LL not used in layout.ts

[gterras]

Hi,

Is there a specific reason for locals.LL not to be used in https://github.com/ivanhofer/typesafe-i18n-demo-sveltekit/blob/main/src/routes/%2Blayout.ts ?

I don't really understand the hassle of importing LL in this file since +layout.server.ts could have returned locals.LL.

Is this for performance reasons? Or reactivity reason in case of a locale change?

Thanks

[gterras]

Cannot stringify a function (data.LL) might be the reason why

[ivanhofer]

You can only access locals in .server.ts files.
The reason to not returning all translations via data props is simple: SvelteKit would need to serialize your full dictionary and your browser would download it again each time you refresh the page. Doing it via the loadLocaleAsync function, makes sure that a real NetworkRequest get's made. The dictionary file will be cached by your browser until you modify it and the hash of that file changes (handled automatically by vite).

From a performance standpoint the SvelteKit implementation is highly optimized. Other platforms like NextJS don't offer an elegant solution to the problem of loading dictionaries while offering SSR.

[gterras]

Thanks for this this makes sense. After reading a few threads about this (including the i18n thread on sveltekit repo and what you said there) and realizing SSRed translation is a complicated topic I think I will stick to in-component translations since it is easy to accidentally mess it up in load function (forgetting parent await or such). The dot notation access you wrote in my other thread will greatly help for this.