emacs-orgmode@gnu.org archives
 help / color / mirror / code / Atom feed
From: Ihor Radchenko <yantar92@gmail.com>
To: Max Nikulin <manikulin@gmail.com>
Cc: emacs-orgmode@gnu.org,  Paul Eggert <eggert@cs.ucla.edu>
Subject: Re: [PATCH v4] org-encode-time compatibility and convenience helper
Date: Wed, 11 May 2022 21:20:51 +0800	[thread overview]
Message-ID: <874k1wjjd8.fsf@localhost> (raw)
In-Reply-To: <f83c0b6e-f605-36fb-89ff-ca805ada5fd4@gmail.com>

Max Nikulin <manikulin@gmail.com> writes:

>> +      (defmacro org-encode-time (&rest time)
>> +        (pcase (length time) ; Emacs-29 since d75e2c12eb
>> +          (1 `(encode-time ,@time))
>> +          ((or 6 9) `(encode-time (list ,@time)))
>> +          (_ (error "`org-encode-time' may be called with 1, 6, or 9 arguments but %d given"
>> +                    (length time)))))
>
> Should it be something like the following?
>
> (signal 'wrong-type-argument (list '(1 6 9) (length time)))
>
> or even
>
> (signal 'wrong-type-argument
>           (list '(lambda (n-args) (memq n-args) '(1 6 9)) (length time)))
>
> Usually "wrong type argument" errors give no clue even related to called 
> function til enabling enter debugger on error and realizing how to 
> reproduce the problem.

The current error is fine. I'd rather propose Emacs to change the "wrong
type argument" message to mention the function name.

>> +              ;; In Emacs-27 and Emacs-28 `encode-time' does not support 6 elements
>> +              ;; list argument so `org-encode-time' can not be outside of `pcase'.
>> +              (pcase-let
>> +                  ((`(,_ ,_ ,_ ,d ,m ,y ,dow . ,_) (decode-time start)))
>> +                (pcase step
>> +                  (`day (org-encode-time 0 0 org-extend-today-until (1+ d) m y))
>> +                  (`week
>> +                   (let ((offset (if (= dow week-start) 7
>> +                                   (mod (- week-start dow) 7))))
>> +                     (org-encode-time 0 0 org-extend-today-until (+ d offset) m y)))
>> +                  (`semimonth (org-encode-time 0 0 0
>> +                                               (if (< d 16) 16 1)
>> +                                               (if (< d 16) m (1+ m)) y))
>> +                  (`month (org-encode-time 0 0 0 month-start (1+ m) y))
>> +                  (`year (org-encode-time 0 0 org-extend-today-until 1 1 (1+ y))))))
>
> I do not like repeating of `org-encode-time' but do not see another way 
> till Emacs-29 will become the lowest supported version.

This is fine. AFAIK, other parts of time handling code is full of conds
and pcases.

>> +	    (org-encode-time
>> +             (apply #'list
>> +                    (or (car time0) 0)
>> +                    (+ (if (eq timestamp? 'minute) n 0) (nth 1 time0))
>> +                    (+ (if (eq timestamp? 'hour) n 0)   (nth 2 time0))
>> +                    (+ (if (eq timestamp? 'day) n 0)    (nth 3 time0))
>> +                    (+ (if (eq timestamp? 'month) n 0)  (nth 4 time0))
>> +                    (+ (if (eq timestamp? 'year) n 0)   (nth 5 time0))
>> +                    (nthcdr 6 time0))))
>>        (when (and (memq timestamp? '(hour minute))
>>  		 extra
>>  		 (string-match "-\\([012][0-9]\\):\\([0-5][0-9]\\)" extra))
>
> I am tempting to write something like
>
>    (let* ((ts (copy-sequence time0))
> 	 (ord (memq timestamp? '(year month day hour minute)))
> 	 (field (and ord (nthcdr (length ord) ts))))
>      (when field
>        (setcar field (+ (car field) n)))
>      (org-encode-time ts))
>
> but I am afraid it will make the code rather obscure.

Yes, the second version is rather hard to understand. The proper
solution would be writing (or using) some high-level time handling
library and then using it in Org. Then, we would not need to deal with
low-level time representations so frequently.

>> +  (org-encode-time
>> +   (append '(0)
>> +           (mapcar
>> +            (lambda (prop) (or (org-element-property prop timestamp) 0))
>> +            (if end '(:minute-end :hour-end :day-end :month-end :year-end)
>> +              '(:minute-start :hour-start :day-start :month-start
>> +                              :year-start)))
>> +           '(nil -1 nil))))
>>  
>>  (defun org-timestamp-has-time-p (timestamp)
>>    "Non-nil when TIMESTAMP has a time specified."
>
> Hardly may be considered as an example of elegant code.

It is ok. You also could do it as

`(0 ,@(mapcar (lambda (prop) ...) (if ...)) nil -1 nil)

AFAIK, there is nothing much you can improve further without using
function composition from dash.el.

Best,
Ihor




  reply	other threads:[~2022-05-11 13:21 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-11 15:22 [DRAFT][PATCH] " Max Nikulin
2022-04-11 17:43 ` Paul Eggert
2022-04-23  8:25 ` Ihor Radchenko
2022-04-23 19:37   ` Paul Eggert
2022-04-24  3:35     ` Ihor Radchenko
2022-04-24 11:34   ` [DRAFT][PATCH v2] " Max Nikulin
2022-04-26  9:07     ` Ihor Radchenko
2022-05-03 12:14       ` [PATCH v3] " Max Nikulin
2022-05-04  9:56         ` Ihor Radchenko
2022-05-04 16:49           ` Max Nikulin
2022-05-05 15:22           ` [PATCH v4] " Max Nikulin
2022-05-07  4:46             ` Ihor Radchenko
2022-05-10 14:31             ` Max Nikulin
2022-05-11 13:20               ` Ihor Radchenko [this message]
2022-05-13 15:14                 ` Max Nikulin
2022-05-14  6:06                   ` Ihor Radchenko

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://www.orgmode.org/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=874k1wjjd8.fsf@localhost \
    --to=yantar92@gmail.com \
    --cc=eggert@cs.ucla.edu \
    --cc=emacs-orgmode@gnu.org \
    --cc=manikulin@gmail.com \
    --subject='Re: [PATCH v4] org-encode-time compatibility and convenience helper' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Code repositories for project(s) associated with this inbox:

	https://git.savannah.gnu.org/cgit/emacs/org-mode.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).