Switch to millisecond resolution (fixes #2)

[eddelbuettel]

This uses the fork by Chris Bove which relies on std::chrono objects instead of time_t which permits the complete flowthrough of millisecond resolution. The R wrapper was updated accordingly and an updated demo is now in the README.md

[dmurdoch]

Runs fine here. Comments:

• The ChangeLog from yesterday has a typo: READNE.md instead of README.md.
• There are lots of whitespace changes in the new src/ulid/* files. Those probably came from the fork you're using, but it might be worth checking just to avoid introducing unnecessary changes.
• You already mentioned the C++17 dependency and need for help updates.

[eddelbuettel]

Thanks for the feedback. As to your bullet points, in order

• will fix the typo (done now in my sources)
• such is life; I copied the files from the aforementioned fork, I won;t hand edit them
• yup (I may just cheat and impose R (>= 4.3.0) which will default to C++17 (adding src/Makevars* oneliners instead)

What platforms did you build? macOS?

[dmurdoch]

Platform was macOS 14.5 (Sonoma), with an M3 chip.

[eddelbuettel]

@markheckmann you may want to give this a whirl, as the (updated) README.md shows we now cover milli-seconds based on the fork switching that std::chrono (that I was unaware of ...)

> library(ulid)
> gen_ulid <- \(sleep) replicate(5, {Sys.sleep(sleep); generate()})
> u <- gen_ulid(.1)
> df <- unmarshal(u)
> data.table::data.table(df)
                        ts              rnd
                    <POSc>           <char>
1: 2024-05-30 16:38:28.588 CSQAJBPNX75R0G5A
2: 2024-05-30 16:38:28.688 XZX0TREDHD6PC1YR
3: 2024-05-30 16:38:28.789 0YK9GKZVTED27QMK
4: 2024-05-30 16:38:28.890 SC3M3G6KGPH7S50S
5: 2024-05-30 16:38:28.990 TSKCBWJ3TEKCPBY0
>