Add {format,print}-recur-rule.

1 files changed, 25 insertions, 0 deletions

diff --git a/module/vcalendar/recurrence/internal.scm b/module/vcalendar/recurrence/internal.scm
index 0f03abc0..caa6ccca 100644
--- a/module/vcalendar/recurrence/internal.scm
+++ b/module/vcalendar/recurrence/internal.scm
@@ -14,6 +14,31 @@
 (define (make-recur-rule interval wkst)
   ((record-constructor <recur-rule> '(interval wkst)) interval wkst))
 
+;; TODO make this part of define-quick-record.
+;; Only "hard" part would be to provide type hints for fields for
+;; string conversions.
+(define (format-recur-rule r)
+  (define (a f)
+    ((record-accessor <recur-rule> f) r))
+  (with-output-to-string
+    (lambda ()
+      (format #t "#<recur-rule>~%")
+      (for-each
+       (lambda (field)
+         (when (a field)
+           (format #t "   ~8@a: ~a~%"
+                   field
+                   ((case field
+                      ((until) (@ (srfi srfi-19 util) time->string))
+                      (else identity))
+                    (a field)))))
+       (record-type-fields <recur-rule>)))))
+
+(define* (print-recur-rule r #:optional (port (current-output-port)))
+  (display (format-recur-rule r) port))
+
+(export format-recur-rule print-recur-rule)
+
 (define weekdays
   '(SU MO TU WE TH FR SA))