refactor: dedupe content between t.d.ts and t.v4.d.ts

[marcalexiei]

At the moment maintaining these two files in sync is a bit painful.
I would like to move the shared content in separate files to reduce maintenance efforts.

Obviously I hope that sometime, in the future, we can remove typescript v4 support 😅

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Moved to a new issue from #2142 to avoid having tasks involving total different aspects of the project (CI vs typescript)

[marcalexiei]

I just noticed that in the typescript documentation is stated that typescript v4 is no longer supported:

https://www.i18next.com/overview/typescript

The newest i18next versions only support TypeScript v5. Older TypeScript versions are not supported any longer with i18next > v23.
To use it with TypeScript v4, use i18next@22.5.1.

This change was made in November with this commit: i18next/i18next-gitbook@106f867

So I'm wondering if we can drop v4 support from the codebase, which implies:

• remove t.v4.d.ts
• typesVersion in package.json
• maybe something else?

[marcalexiei]

@adrai what so you think about this?

[adrai]

Sorry, missed your question completely...
My gut feeling tells me, we should keep the v4 support at least a little bit more... but we don't need to make sure all types functionality is in line with v5 if not possible...

[marcalexiei]

Sorry, missed your question completely...

No problem 🙂

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My gut feeling tells me, we should keep the v4 support at least a little bit more... but we don't need to make sure all types functionality is in line with v5 if not possible...

Gotcha. I'll leave this open open as a reminder to do that in the future 😀