Implement the DATETIME() builtin function

[tmpfs]

Hi,

I really admire the fluent design, it is elegant - thank you!

I was following the documentation here:

https://www.projectfluent.org/fluent/guide/builtins.html

And wanted to try out the DATETIME() function but I got an error:

[ResolverError(Reference("Unknown function: DATETIME()"))]

I thought maybe it was behind a feature flag but a search or the repo and a quick look at the source code didn't yield anything.

Is this function available in the Rust implementation?

[zbraniecki]

Thank you for your kind words!

Unfortunately, not yet. I'm experimenting with it in https://github.com/zbraniecki/unic-datetime and likely it'll end up being developed as part of https://github.com/unicode-org/icu4x

If you need it now, I'd recommend hooking in https://github.com/google/rust_icu which is a wrapper around ICU4C.

[tmpfs]

Thanks for the swift reply and the links. I took a quick look at rust_icu and it appears it would be non-trivial to integrate going via fluent (I suppose I would need to define the DATETIME function which would call out to the rust_icu_udat crate). It is not urgent for this project but would love to see it land as part of project fluent! Once my current project is stable I might be able to take a look into it some more and will let you know if I make any progress.

In the meantime it might be worth making a note in the documentation about lack of DATETIME in fluent-rs; thanks very much!

[TheRawMeatball]

Has there been any recent progress on this?

[zbraniecki]

ICU4X is approaching 1.0 release. Once it is released, we'll be able to add this as an optional dependency and enable dates here.

[stevepryde]

Any update on this? ICU4X is now at v1.1.0

[g2p]

I have published a crate with the necessary glue:
https://docs.rs/fluent-datetime
https://lib.rs/crates/fluent-datetime

[alerque]

@g2p Would you consider working on a contribution following up on #353 so that the add_buildits() can be expanded to include a DATETIME()? If so lets definitely consider building that on the ICU4X work than is pending in other branches too since it seems pletty clear that's the way this is headed.