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+open Sexplib0.Sexp_conv
+
+(* The single stable result schema (parent spec §2). *)
+type ('s, 'r) t = {
+  date : Date.t;
+  rite : string;
+  temporal : ('s, 'r) Temporal.t;
+      (** embedded, not flattened: it is already a coherent unit with its own
+          invariants, and re-listing season/week/weekday here would create two
+          places for them to disagree *)
+  observed : 'r Celebration.t;
+  commemorations : ('r Celebration.t * Precedence.privilege) list;
+  transferred_in : 'r Celebration.t option;
+      (** arrived here from an impeded day *)
+  transferred_out : ('r Celebration.t * Date.t) list;
+      (** celebrations that left this day, and where each one went. A list,
+          not an option: RG 97-98 has coinciding I-class feasts transfer
+          "in order" -- plural -- so a day can lose more than one. Asymmetric
+          with [transferred_in] deliberately: a day receives at most one
+          arrival, because RG 96 sends each departure to the next day that
+          is not I or II class, and the first to arrive occupies it. *)
+  omitted : ('r Celebration.t * string) list;
+      (** with the reason, never silent -- Task 12's no-celebration-lost
+          invariant reads this *)
+  citations : Citation.t list;  (** always empty until Plan 4 *)
+}
+[@@deriving sexp]