Re: Weekday abbreviations in output of cal(1)

[neitzel%hackett.marshlabs.gaertner.de@localhost (Martin Neitzel)]

> > I am not 100% sure how to do the job with NetBSD's date(1).  I may
> > be just lucky with
> > 	% date -d '+1 month 1 thu'
> > 	Thu Aug  6 00:00:00 CEST 2020
> > because today is the 1st of July.
>
> Why wait? Try [...]

Because yesterday was unsuitable to check for the ambiguity how the second
"1" in that expression is actually parsed.  Is it parsed as in:

	(+1 month 1) thu

as in "go next month, its 1st, forward to Thursday",
or is it:

	+1 month (1 thu)

as in "go next month (same day as today, i.e. 2nd NOW), forward 1 thu".
This would skip the weekdays already passed, such as the upcoming
Saturday on Aug 1st.   And indeed:

	$ date -d '+1 month 1 sat'
	Sat Aug  8 00:00:00 CEST 2020

That is: the expression is, alas, *not* good enough to compute the
"first $WEEKDAY of next month".  I am at a loss how to do this with
NetBSD's date(1).

This wasn't decidable yesterday, and I wrote:

> > I better recheck this in a fortnight.

because the "Thursday" check, one-shot or ranged as in

	> for i in 1 2 3 4 5 6 7 8 9 10
	> do
	> date -d "+$i month 1 thu"
	> done

will not fail immediately but more and more blatantly as we progress
into the month.

						Martin Neitzel

PS:  The () in the date expressions above are just to illustrate
possible parsings.  The actual date command treats "(stuff)" as
a comment.