[PATCH] ISO weeks for calendar

[Mats Lidell]

>>>>> Michael wrote:

Michael> several moons ago I hacked up calendar mode to display the
Michael> ISO or business weeks within the calendar.

ISO weeks is a good thing. I have been wanting them too. Nice that you
have given it a try.

Michael> Perhaps some kind soul (who has deeper lisp knowledge than I
Michael> have) may find this useful and can do a review of this piece
Michael> of code. 

I don't know about deep lisp knowledge but I found one or possibly two
problems when I tried the patch.

======================================================================
* 1 -- The function calendar-iso-from-absolute is not loaded. Added an
  autoload for that.

Index: cal-iso.el
===================================================================
RCS file: /pack/xemacscvs/XEmacs/packages/xemacs-packages/calendar/cal-iso.el,v
retrieving revision 1.6
diff -u -r1.6 cal-iso.el
--- cal-iso.el	16 Apr 2007 02:12:25 -0000	1.6
+++ cal-iso.el	21 Jul 2007 22:49:51 -0000
@@ -64,6 +64,7 @@
        (* 7 (1- week))
        (if (= day 0) 6 (1- day)))))
 
+;;;###autoload
 (defun calendar-iso-from-absolute (date)
   "Compute the `ISO commercial date' corresponding to the absolute DATE.
 The ISO year corresponds approximately to the Gregorian year, but
 weeks

======================================================================
* 2 -- The week numbers are accepted as valid dates causing
  insert-diary-entry to behave odd. Should be "Not a valid date" just
  as if doing the same on other bad positions in the buffer I think.

  This is what I came up with -- Ignore the match if in iso week
  columns. Please check and improve. (Partial patch: Just the defun
  calendar-insert-indented included.)

Index: calendar.el
===================================================================
RCS file: /pack/xemacscvs/XEmacs/packages/xemacs-packages/calendar/calendar.el,v
retrieving revision 1.16
diff -u -r1.16 calendar.el
--- calendar.el	10 Jul 2007 22:52:24 -0000	1.16
+++ calendar.el	21 Jul 2007 22:49:52 -0000
 (defun calendar-insert-indented (string indent &optional newline)
   "Insert STRING at column INDENT.
@@ -2614,7 +2644,7 @@
   ;; changes allowing that to be in another frame.
 ;  (if (not (number-or-marker-p displayed-month))
 ;      nil
-  (let* ((segment (/ (current-column) 25))
+  (let* ((segment (/ (current-column) (if calendar-display-iso-week-numbers 26 25)))
          (month (% (+ displayed-month segment -1) 12))
          (month (if (= 0 month) 12 month))
          (year
@@ -2623,7 +2653,9 @@
            ((and (=   1 month) (= segment 2)) (1+ displayed-year))
            (t displayed-year))))
     (if (and (looking-at "[ 0-9]?[0-9][^0-9]")
-             (< 2 (count-lines (point-min) (point))))
+             (< 2 (count-lines (point-min) (point)))
+	     (or (not calendar-display-iso-week-numbers)
+		 (> (current-column) (+ 5 (* 26 segment)))))
         (save-excursion
           (if (not (looking-at " "))
                    (re-search-backward "[^0-9]"))

Michael> I hope to see it in the calendar package someday.

This patch looks promising for the upstream version of calendar. You
might want to try to get it in there.

Yours
-- 
%% Mats