Fixes 'keyof T' type example

[aleph-naught2tog]

Fixes #29249 from the TypeScript repository

[guillaumep]

@aleph-naught2tog Actually TypeScript type as (string | number)[] and not string[].

This atypical result would certainly require some explanation (it confuses me a lot).

[DanielRosenwasser]

The explanation is that because string index signatures implicitly handle indexing with numbers, keyof also returns number in the output type.

[aleph-naught2tog]

@DanielRosenwasser I think I'm confused; which is the correct typing then? I had read the issue as being that it wasn't string[] so the fix was to make it that, but I can totally change it 😁

[RyanCavanaugh]

Thank you for contributing to the TypeScript Handbook!

We are currently working through a large backlog of open PRs. As part of this, we're asking authors of PRs with active merge conflicts to assess if their changes are still needed, and if so, open a new PR.

For transparency, we are also working on a full-scale reimagining of the Handbook (see the TypeScript Roadmap), meaning we are largely closing down work on the current version of the Handbook. Typo fixes are always appreciated, but any new content should likely wait until the new Handbook is available so that it can be more naturally adapted to that format.

[tommck]

So... it's been 5 months... still not updating the old content? Do we have an ETA on the new handbook?

[orta]

I just merged a PR like this, so the fix will appear in the new site on the next deploy