date in yaml frontmatter from an evaluated R expression?

[rkrug]

Hi
I use regularly in my Rmarkdown documents

date: "`r Sys.time()`"

But this results in a quarto document in an

PUBLISHED
Invalid Date

How can I use the current date (and possibly also the tome) for the quarto document in the frontmatter?

Thanks

[dragonstyle]

Hi - we've just been doing some work in this area, so great timing! What version of Quarto are you using? Recent versions should support that syntax for documents.

In addition, the very latest version also supports either today or last-modified which provide the current day or the last modified date of the input qmd respectively. e.g.:

--- 
date: today
---

or

--- 
date: last-modified
---

[rkrug]

Brilliant - I love it that problems are solved before they bother me...

I am using quarto 0.9.123, installed using home-brew.

[rkrug]

Nice - upgraded to 0.90128 and today and last-updated are working.

One follow up question: would it be possible to also support to have the time in there?

[dragonstyle]

There may be two things in play. For 'today' we currently zero the time (assuming users likely typically mean this day). For last-modified we do preserve the time. It may just be the formatter that is omitting the time. If you'd like you can confirm by using the date-format: key to tinker with the format. We just added news docs for this here:

https://quarto.org/docs/reference/date-format.html

If you think a version of 'today' with a timestamp would be beneficial, we could consider also adding support for 'now' which would include a timestamp...

[rkrug]

It works with setting the date format:

---
date: last-modified 
date-format: "DD MMM YYYY, HH:mm"000
---

But I think a "now" timestamp would be beneficial, as in the case of for example reports of data processing, the time is useful when e.g. data is generated in hourly intervalls.

Thanks a lot,

Rainer

[eyayaw]

---
date: today
date-format: long #"MMMM DD, YYYY" # "`r format(Sys.Date(), '%B %d, %Y')`"
---

Does not seem to work for format: pdf. How does dynamic date work in pdf output?

> quarto version: quarto-0.9.228-macos.pkg (Pkg)

[cderv]

@eyayaw I can reproduce. Let's open an issue for this. #615

[rkrug]

Why can't I mark @dragonstyle reply as the answer?

[dragonstyle]

Ok, we'll add a case for 'now' as well- thanks for the feedback! I'm not sure why - perhaps you can only mark the root answers vs replies...