calendar-goto-iso-week

[Emilio Lopes]

Emacs' Calendar already has `calendar-goto-iso-date', but it
requires too much user input when you just want to jump to
a given week.  The following command should help you in such
situations.

I bind it to "g w" in `calendar-mode'.

(defun calendar-goto-iso-week (week year)
  "Move cursor to ISO week number WEEK of year YEAR.
Interactively uses the \"current\" year and just asks for a week number."
  (interactive
   (progn 
     (require 'cal-iso)
     (let* ((year (extract-calendar-year (calendar-cursor-to-date t)))
            (no-weeks (extract-calendar-month
                       (calendar-iso-from-absolute
                        (1-
                         (calendar-dayname-on-or-before
                          1 (calendar-absolute-from-gregorian
                             (list 1 4 (1+ year))))))))
            (week (calendar-read
                   (format "ISO calendar week (1-%d): " no-weeks)
                   '(lambda (x) (and (> x 0) (<= x no-weeks))))))
       (list week year))))
  (calendar-goto-iso-date (list week calendar-week-start-day year)))