1 files changed, 7 insertions, 1 deletions
diff --git a/lib/kernel/temporal.mli b/lib/kernel/temporal.mli
index 055f9aa..9113dba 100644
--- a/lib/kernel/temporal.mli
+++ b/lib/kernel/temporal.mli
@@ -2,7 +2,13 @@
     the temporal cycle's own office for it. *)
 type ('s, 'r) t = {
   season : 's;
-  week : int option;  (** [None] for named days outside a numbered week *)
+  week : int option;
+      (** [None] exactly when the date falls outside every numbered week the
+          rite defines (e.g. a season with no week numbering at all, or a
+          transitional span between two numbered runs). A day being *named*
+          is not by itself a reason for [None]: a named day that sits inside
+          a numbered season run must carry that run's week the same as any
+          other day in it. *)
   weekday : Date.weekday;
   office : 'r Celebration.t;
 }