[Question] Boundaries of the week and month

[treylav]

Hello!

First of all — great project, and thanks for the fresh take on the problem. I’ve started replacing usage the standard library in my codebase with whenever and gradually throwing away a bunch of my own hacky helpers.

However, I have an example I couldn’t immediately replace: functions that return the “boundaries”, "spans" of weeks and months — the first and last days of a week, and the first and last days of a month.

Of course, once you’ve got deltas, nothing is impossible, but my current solution still looks like something I came up with while using the standard library:

now = whenever.Date.today_in_system_tz()

first_day_of_month = now.replace(day=1)
last_day_of_month = first_day_of_month + months(1) - days(1)

monday_of_week = now - days(now.day_of_week().value - 1)
sunday_of_week = monday_of_week + days(6)

Maybe I’ve missed something in the documentation and there’s a more idiomatic way to do this?

Thanks in advance.

P.S. Really waiting for ranges and intervals too!

[ariebovenberg]

Hi @treylav thanks for posting. I have given this some thought, although my focus at the moment is on getting the last breaking changes out (also relating to deltas).

For your use case, I do expect to improve support. Note that round() already does what you want for hours/minutes/seconds. For years/months/days it gets a bit more complicated, that's why there's no support yet. I might integrate them into round(), or add methods start_of(<unit>) and end_of(<unit>). There'd have to a separate API for the next weekday case.

I will take some time to get this API right, as I want to avoid having too many methods, which is confusing and error-prone

[treylav]

Thanks, round() was my second option, but I couldn't find a way to make it work — I understand why now. 🙂

I don’t want to enforce concepts from other libraries, but I find the way Arrow did something similar pretty neat:

arrow.utcnow().span('hour')
(<Arrow [2013-05-07T05:00:00+00:00]>, <Arrow [2013-05-07T05:59:59.999999+00:00]>)

Still, it fits much better if ranges are implemented first.
Anyway, that’s my very naive take — you’re seeing the bigger picture.

I’ll keep an eye on the updates — good luck!