Subject: Re: bug#78120: 31.0.50; Calendar is not reliable with its marking

From: Eli Zaretskii <[email-masked]>
Date: Tue, 06 May 2025 14:25:34 +0300

> From: Manuel Giraud <[email-masked]>
> Cc: Eli Zaretskii <[email-masked]>,  [email-masked]
> Date: Tue, 06 May 2025 08:23:58 +0200
> 
> Michael Heerdegen <[email-masked]> writes:
> 
> > Manuel Giraud <[email-masked]> writes:
> >
> >> I think a better way would be to use the overlay priority and be able to
> >> select from the diary date.
> >
> > What do you mean by "select from the diary date"?
> 
> Sorry, I wasn't clear.  At least for diary dates entered in sexp forms,
> one can add an optional face (or a mark string) like this:
> 
> %%(diary-anniversary 11 5 1955 'error) Marty arrives
> 
> So maybe, we could have another optional parameter to add an overlay
> priority value.

IMO, it makes little sense to bother users with overlay priorities.
That's a highly technical issue, and defining a good value requires to
have intimate knowledge about the relevant features and functions.

Why cannot the priority come from the code itself?  If you are saying
that it is impossible to decide which face should haver precedence,
something that I find very surprising, then some kind of user option
that allows to set the priority of one overlay higher or lower than
the other (without actually asking users to provide the priority
itself) would make more sense.  But up front, I'd be very surprised to
hear that we are unable to make the correct decision without burdening
the users with these decisions.  If that is what you think, please try
to explain in detail why such a decision is impossible.  Surely, out
of the two faces one conveys information that is more important than
the other?