(** EF (1962) season and rank vocabulary. *)

type season =
  | Advent
  | Christmastide
  | Time_after_epiphany
  | Septuagesima
  | Lent
  | Passiontide
  | Paschaltide
  | Time_after_pentecost
[@@deriving sexp]

type rank = Class1 | Class2 | Class3 | Class4 [@@deriving sexp]

val seasons : season list
val ranks : rank list
val season_to_string : season -> string
val season_of_string : string -> season option

(** The word used when building a slug. Deliberately differs from
    {!season_to_string} for [Christmastide] ("christmas") and [Paschaltide]
    ("easter"), because slugs are lectionary keys adopted verbatim from lectio. *)
val season_slug_word : season -> string

val rank_to_string : rank -> string
val rank_of_string : string -> rank option
val vocab : (season, rank) Colitur_kernel.Vocab.t