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+(** The rite-parameterised resolver: RG 91 says who wins, RG 92-95 says what
+ happens to the loser, RG 108-111 says how many commemorations are admitted.
+ Three separate rite-supplied functions, because the loser's fate depends on
+ the loser's own rank, not the winner's -- conflating them would resist
+ extension to a second rite. *)
+
+(** Which of the day's two office streams a candidate came from. *)
+type origin = Temporal | Sanctoral [@@deriving sexp]
+
+(** RG 111: an admitted commemoration's own standing, distinct from its rank. *)
+type privilege = Privileged | Ordinary [@@deriving sexp]
+
+(** What becomes of a losing candidate. *)
+type disposition =
+ | Omit (** yields with no trace in the day's celebration *)
+ | Commemorate of privilege (** kept as a commemoration of the observed day *)
+ | Transfer (** moved to the next free day (RG 92-95) *)
+ | Repose (** kept only in a votive/private sense; not commemorated today *)
+[@@deriving sexp]
+
+(** A celebration together with the office stream it was drawn from. Parameterised
+ by the rite's rank type only, matching {!Celebration.t}. *)
+type 'r candidate = { cel : 'r Celebration.t; origin : origin } [@@deriving sexp]
+
+(** The day a resolution is computed for. Parameterised by the rite's season
+ type only -- a context has no rank of its own. *)
+type 's context = { date : Date.t; season : 's; weekday : Date.weekday }
+
+(** The rite's three resolution functions. *)
+type ('s, 'r) rules = {
+ band : 's context -> 'r candidate -> int;
+ (** RG 91: orders candidates for the day; lower wins. *)
+ disposition : winner:'r candidate -> loser:'r candidate -> disposition;
+ (** RG 92-95: the loser's fate, which depends on the loser's own rank. *)
+ admit :
+ observed:'r candidate ->
+ ('r candidate * privilege) list ->
+ ('r candidate * privilege) list;
+ (** RG 108-111: how many commemorations are admitted, and in what order;
+ anything filtered out here is recorded in {!resolution.omitted}, not
+ dropped. *)
+}
+
+(** The outcome of resolving one day's candidates. *)
+type 'r resolution = {
+ observed : 'r candidate;
+ commemorations : ('r candidate * privilege) list;
+ deferred : 'r candidate list;
+ omitted : ('r candidate * string) list; (** each with a reason *)
+}
+
+(** Total: the temporal candidate is passed separately, so there is no
+ empty-candidate case. Ties break on slug, so the result never depends on
+ input order. A [Commemoration_only] celebration is held out of the contest
+ and can never be [observed]. Every input candidate appears exactly once in
+ [observed], [commemorations], [deferred] or [omitted] — nothing is dropped
+ silently. *)
+val resolve :
+ ('s, 'r) rules -> 's context -> temporal:'r candidate ->
+ sanctoral:'r candidate list -> 'r resolution