Add support for number range formatting

[vimtor]

Is your feature request related to a problem? Please describe.

I want to format a range of numbers using the existing number range format API:

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/NumberFormat/formatRange

Describe the solution you'd like

Either an option to the .number method in the Formatter object or a new numberRange method.

Describe alternatives you've considered

I've considered using the API directly, but it is only supported in Node.js 19. The latest version available in Vercel is Node.js 18.

[amannn]

Thanks for the feature request @vimtor! I think useFormatter().numberRange(startRange, endRange, options?) would be a great addition.

However, we rely on polyfills, so in regard to your question about Node.js 18 support, you'd have to polyfill the API anyway. Would that work for you?

[vimtor]

Yes, @amannn! That would be a great addition :)

Regarding the polyfill, I assume the polyfill will be included with the library, right? If that is the case, it would work 100%

[amannn]

next-intl doesn't do any polyfilling in order to reduce the library size (see the runtime requirements). In case we add support for number range formatting, we should add an entry for this API in the runtime requirements docs.

Would you be interested in contributing this feature? :)

[vimtor]

Yes! I would love to contribute to this feature.

Would it be better to wait until the RSC integration is merged, right?

[amannn]

Great to hear, I'm fine either way!

You can either:

1. Make a PR against the main branch and we'll publish this in a minor version. Afterward, I'll rebase the RSC branch.
2. Make a PR against the RSC branch and we'll release this as part of the 3.0 version.

I hope to stabilize the RSC integration in the next few weeks, so there shouldn't be much difference practically.

[amannn]

Superseded by #774. We can still add this if there's need for this functionality.