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(** Ecclesiastical Easter. See docs/research/rules-register.md §0.
    Both functions are total for a year in 1583..9999. *)

(** Easter Sunday by the Gregorian reckoning (OF + EF). *)
val gregorian_easter : int -> Date.t

(** Easter-relative movable-feast anchors (register section 0), Gregorian
    reckoning: Ash Wednesday = Easter-46 (Wed), Palm Sunday = Easter-7,
    Ascension = Easter+39 (Thu), Pentecost = Easter+49, Corpus Christi =
    Easter+60 (Thu, EF). *)
val ash_wednesday : int -> Date.t
val palm_sunday : int -> Date.t
val ascension : int -> Date.t
val pentecost : int -> Date.t
val corpus_christi : int -> Date.t

(** Easter Sunday by the Julian reckoning, returned as the equivalent proleptic
    Gregorian date (for future eastern rites; EF/OF use {!gregorian_easter}). *)
val julian_easter : int -> Date.t