From 60e87914718dd2c8e69bb89d8cc48d6bef9bfc74 Mon Sep 17 00:00:00 2001 From: Lukasz Kasprzak Date: Sat, 22 Aug 2026 16:40:07 +0200 Subject: feat(ef): implement the calendarium's bissextile February shift The Missale Romanum's calendarium footnote for February (LT.txt:5011-5014, scan-corroborated scan2.txt:3050-3058): in a leap year the sixth kalends of March (24 February) is doubled rather than a 29th day appended, so St Matthias moves 24->25 February and St Gabriel of Our Lady of Sorrows 27->28, with 24 February itself carrying no fixed office that year. data/ef/expected-divergences-lms.sexp entry L3 tracked this as an open gap. Implemented as the rubric's own general mechanism (every fixed entry from 24 through 28 February shifts one civil day later in a leap year), not as "move these two named saints": the two readings are indistinguishable on shipped data (nothing else is fixed in that window) and diverge only for a future --overlay entry in the same range, which the mechanism reading covers correctly and a two-saints special case would not. This project has already been bitten once (RG 16(a)) by a rule implemented against shipped data's coincidental shape rather than the rubric itself. Kernel stays rite-agnostic: Rite.t gains a fixed_key field (Date.t -> (int * int) option), the same seam easter already establishes, read only by Layer.on_date's FIXED half -- the movable half (Easter_offset/Nth_weekday) is untouched. Default is the identity mapping, an optional argument on on_date, so every existing caller and every rite that supplies nothing is byte-identical to before this field existed. Date.is_leap is exposed in date.mli (already existed in date.ml) so the rite reads the kernel's own single-sourced leap-year definition. The EF implementation lives in Rite_ef.Temporal_ef.bissextile_fixed_key, fully cited, wired into Rite_ef.context. Blast radius, measured over the full 1583-9999 domain (Calendar.year run twice per civil year, real fixed_key vs identity, every day diffed): all 2,041 leap years in the domain show a visible change for each saint; 6,983 individual liturgical days change total, zero unclassified, across four shapes (Matthias vacates 24 Feb in 1,803 years / occupies 25 Feb in 1,811; Gabriel vacates 27 Feb in 1,699 / occupies 28 Feb in 1,670). L3's own prior estimate (1,650 years, observed-outright only) is confirmed close on the same definition (1,677 measured); the broader observed-or- commemorated count is higher, not lower, showing the narrow estimate undercounted visible impact rather than overcounting it. The lectio differential (2005-2050 fixture) gains a new cited entry, C40 in data/ef/expected-divergences.sexp: lectio implements no such shift, so every leap year in its window now diverges on the two shifted days (21 rows, not the naive 44 -- the comparator never compares commemorations, so a side where the shifted saint has zero comparator-visible footprint on both engines produces no row). The LMS Ordo's 2023-2024 fixture -- the window L3 was originally found in -- now matches on the Creed comparison; its formulary-override bucket count is corrected 182->181 (24 February leaves the counted Proper population, becoming Own_slug-sourced). The missalemeum oracle fixtures (2026-2027, 2038, 2035) cover no leap year and are unaffected. L3 is closed: converted from an active allow-list record to a prose closure paragraph (L1's own precedent), citation preserved verbatim, fix and measured blast radius recorded. The id-list assertion narrows to [L4] alone, and the now-dead "2024-02-24" -> "L3" date mapping is removed. Six golden values pinned across four new test cases: Matthias in a leap year (both the vacated and occupied sides) and a common-year control; Gabriel likewise, deliberately choosing a leap year where he is admitted only as an ordinary commemoration rather than winning outright, a different shape from Matthias's. Mutation-tested: forcing fixed_key back to identity reddens exactly five test cases -- the differential's Layer C count-pin (C40 drops to 0 actual vs 21 expected), the LMS Ordo's Creed and formulary-bucket checks, and both new golden pins -- confirming the tests actually exercise the fix. Reverted; dune test, the exhaustive sweep, and make check are all green. --- lib/kernel/calendar.ml | 7 +++-- lib/kernel/date.mli | 7 +++++ lib/kernel/layer.ml | 8 +++-- lib/kernel/layer.mli | 13 ++++++-- lib/kernel/rite.ml | 1 + lib/kernel/rite.mli | 27 +++++++++++++++++ lib/kernel/validate.ml | 2 +- lib/rites/rite_ef/rite_ef.ml | 4 +++ lib/rites/rite_ef/temporal_ef.ml | 62 +++++++++++++++++++++++++++++++++++++++ lib/rites/rite_ef/temporal_ef.mli | 11 +++++++ 10 files changed, 134 insertions(+), 8 deletions(-) (limited to 'lib') diff --git a/lib/kernel/calendar.ml b/lib/kernel/calendar.ml index d55e38d..db6c58e 100644 --- a/lib/kernel/calendar.ml +++ b/lib/kernel/calendar.ml @@ -79,7 +79,7 @@ let resolve_with_injected ?(suppressed = no_suppression) (rite : ('s, 'r) Rite.t { Precedence.cel = temporal.Temporal.office; origin = Precedence.Temporal } in let natural = - Layer.on_date idx date + Layer.on_date ~fixed_key:rite.Rite.fixed_key idx date |> List.map (fun (e : 'r Layer.entry) -> { Precedence.cel = e.Layer.cel; origin = Precedence.Sanctoral }) in @@ -339,7 +339,7 @@ let rg33_suppressed (rite : ('s, 'r) Rite.t) (idx : 'r Layer.index) Array.iter (fun date -> let candidates = - Layer.on_date idx date + Layer.on_date ~fixed_key:rite.Rite.fixed_key idx date |> List.map (fun (e : 'r Layer.entry) -> { Precedence.cel = e.Layer.cel; origin = Precedence.Sanctoral }) in @@ -529,7 +529,8 @@ let build_day (rite : ('s, 'r) Rite.t) (idx : 'r Layer.index) | None -> [] | Some slugs -> let on_date = - Layer.on_date idx date |> List.map (fun (e : 'r Layer.entry) -> e.Layer.cel) + Layer.on_date ~fixed_key:rite.Rite.fixed_key idx date + |> List.map (fun (e : 'r Layer.entry) -> e.Layer.cel) in let temporal_office = temporal.Temporal.office in (temporal_office :: (on_date @ List.map (fun c -> c.Precedence.cel) arrived)) diff --git a/lib/kernel/date.mli b/lib/kernel/date.mli index 2f632c8..0e86d54 100644 --- a/lib/kernel/date.mli +++ b/lib/kernel/date.mli @@ -14,6 +14,13 @@ val month : t -> int val day : t -> int val weekday : t -> weekday +(** Proleptic Gregorian leap-year test: divisible by 4, except a century year + not divisible by 400. The same rule {!make}/{!days_in_month} already use + internally to admit 29 February -- exposed so a rite can key its own + calendar-reckoning rules (e.g. a kalends-doubling convention) off the + identical, single-sourced definition rather than re-deriving it. *) +val is_leap : int -> bool + (** [to_rata]/[of_rata] expose the underlying day-count (days since 1970-01-01); [of_rata] and [add_days] are unbounded total arithmetic (they may denote a year outside 1583..9999 — only [make] enforces the domain). *) diff --git a/lib/kernel/layer.ml b/lib/kernel/layer.ml index f069546..2a072f0 100644 --- a/lib/kernel/layer.ml +++ b/lib/kernel/layer.ml @@ -73,8 +73,12 @@ let index t ~easter ~years = Hashtbl.iter (fun k v -> Hashtbl.replace movable k (canonical v)) movable; { fixed; movable } -let on_date idx date = - let f = try Hashtbl.find idx.fixed (Date.month date, Date.day date) with Not_found -> [] in +let on_date ?(fixed_key = fun d -> Some (Date.month d, Date.day d)) idx date = + let f = + match fixed_key date with + | None -> [] + | Some k -> ( try Hashtbl.find idx.fixed k with Not_found -> []) + in let m = try Hashtbl.find idx.movable (Date.to_rata date) with Not_found -> [] in match m with [] -> f | _ -> canonical (f @ m) diff --git a/lib/kernel/layer.mli b/lib/kernel/layer.mli index ab6e56b..a71e113 100644 --- a/lib/kernel/layer.mli +++ b/lib/kernel/layer.mli @@ -36,8 +36,17 @@ type 'r index val index : 'r t -> easter:(int -> Date.t) -> years:int list -> 'r index (** Entries falling on [date], fixed and movable together, in the layer's - canonical slug order. *) -val on_date : 'r index -> Date.t -> 'r entry list + canonical slug order. + + [fixed_key] answers "which (month, day) does the FIXED half look up for + this civil date", defaulting to the identity [Some (Date.month date, + Date.day date)] -- exactly today's behaviour, for a caller that supplies + nothing. A rite's own kalends-reckoning convention (see {!Rite.t}'s + [fixed_key] field) is threaded through here rather than applied to + [date] itself, so it touches ONLY the fixed table: the MOVABLE half + (keyed by rata die, via {!Date_spec.Easter_offset}/{!Date_spec. + Nth_weekday}) always uses [date] unchanged. *) +val on_date : ?fixed_key:(Date.t -> (int * int) option) -> 'r index -> Date.t -> 'r entry list (** Loads a layer from a sexp file. Parse and validation failures come back as [Error], never as an exception. *) diff --git a/lib/kernel/rite.ml b/lib/kernel/rite.ml index 4999fc2..738785a 100644 --- a/lib/kernel/rite.ml +++ b/lib/kernel/rite.ml @@ -8,6 +8,7 @@ type ('s, 'r) t = { temporal : Date.t -> ('s, 'r) Temporal.t; anchors : int -> (string * Date.t) list; easter : int -> Date.t; + fixed_key : Date.t -> (int * int) option; rules : ('s, 'r) Precedence.rules; season_runs : 's list; transfer_target : diff --git a/lib/kernel/rite.mli b/lib/kernel/rite.mli index 39538d0..0dcf17e 100644 --- a/lib/kernel/rite.mli +++ b/lib/kernel/rite.mli @@ -17,6 +17,33 @@ type ('s, 'r) t = { into rite-agnostic code and be silently wrong for a Julian-reckoning rite. Read by {!Layer.index} to resolve {!Date_spec.Easter_offset}. *) + fixed_key : Date.t -> (int * int) option; + (** The (month, day) under which a FIXED sanctoral entry ({!Layer.on_date}) + is looked up for this civil date. [Some (month, day)] identity for + every rite with no reason to differ -- a Byzantine or other + non-Roman rite supplies nothing beyond that, and its output is + therefore byte-identical to a rite that predates this field + entirely. [None] means no fixed entry can ever be found for this + date, regardless of what {!Layer.index} holds. + + Exists for the Roman calendarium's own bissextile (leap-year) + footnote (February, docs/research/LT.txt:5011-5014): the + intercalary day is inserted by DOUBLING the sixth kalends of March + (civil 24 February in a common year), not by appending a 29th day + at the month's end, so every fixed feast dated at or after that + kalends position is kept one civil day later than usual, and 24 + February itself carries no fixed entry that year. This is a fact + about the ROMAN rite's own kalends reckoning, not a universal + computus rule -- a rite with no such convention (or none at all, + the default above) must not have it hardcoded into rite-agnostic + code, the same reason {!easter} above is rite-supplied rather than + chosen here. See rite_ef/temporal_ef.ml's [bissextile_fixed_key] + for the concrete Roman implementation and its full citation. + + Deliberately untouched: the MOVABLE half of {!Layer.on_date}'s + lookup ({!Date_spec.Easter_offset}, {!Date_spec.Nth_weekday}) -- + this field's contract is fixed-date reckoning only, and nothing in + the calendarium footnote concerns Easter-relative dates. *) rules : ('s, 'r) Precedence.rules; season_runs : 's list; (** the expected run-length-compressed season sequence over one liturgical diff --git a/lib/kernel/validate.ml b/lib/kernel/validate.ml index ce48615..f523b39 100644 --- a/lib/kernel/validate.ml +++ b/lib/kernel/validate.ml @@ -239,7 +239,7 @@ let run (rite : ('s, 'r) Rite.t) (layer : 'r Layer.t) ~year = let expected : (string, int) Hashtbl.t = Hashtbl.create 64 in List.iter (fun date -> - Layer.on_date idx date + Layer.on_date ~fixed_key:rite.Rite.fixed_key idx date |> List.iter (fun (e : 'r Layer.entry) -> bump expected (Slug.to_string e.Layer.cel.Celebration.slug))) days; diff --git a/lib/rites/rite_ef/rite_ef.ml b/lib/rites/rite_ef/rite_ef.ml index e48ff33..ba1274b 100644 --- a/lib/rites/rite_ef/rite_ef.ml +++ b/lib/rites/rite_ef/rite_ef.ml @@ -39,6 +39,10 @@ let context ~lectionary ~commons : (Vocab_ef.season, Vocab_ef.rank) Rite.t = Julian-reckoning rite can supply {!Computus.julian_easter} instead. Read by [Layer.index] for [Date_spec.Easter_offset]. *) easter = Colitur_kernel.Computus.gregorian_easter; + (* The calendarium's own bissextile footnote (February, LT.txt:5011-5014): + see {!Temporal_ef.bissextile_fixed_key} for the full citation and + mechanism. Read by [Layer.on_date]'s fixed half only. *) + fixed_key = Temporal_ef.bissextile_fixed_key; rules = { Precedence.band = Precedence_ef.band; disposition = Precedence_ef.disposition; diff --git a/lib/rites/rite_ef/temporal_ef.ml b/lib/rites/rite_ef/temporal_ef.ml index c16732b..1c916f4 100644 --- a/lib/rites/rite_ef/temporal_ef.ml +++ b/lib/rites/rite_ef/temporal_ef.ml @@ -1158,6 +1158,68 @@ let anchors y = | Some d -> [ ("ef-holy-name-sunday", d) ] | None -> [ ("ef-holy-name", holy_name_fallback_date y) ]) +(* The Missale Romanum's own CALENDARIUM table, February, footnote + (docs/research/LT.txt:5011-5014, scan-corroborated at + docs/research/scan2.txt:3050-3058, where OCR mangles it to + "bi&sextili"/"Matthue"/"Cabrielis" -- transcription and scan agree, so + this rests on two witnesses of the same document): + + "In anno bissextili mensis februarius est dierum 29, et festum S. + Matthiae celebratur die 25 februarii, ac festum S. Gabrielis a + Virgine perdolente 28 februarii, et bis dicitur sexto calendas, id + est die 24 et die 25; et littera dominicalis, quae assumpta fuit in + mense ianuario, mutetur in praecedentem..." + + In a leap year February has 29 days, St Matthias is kept on 25 February + (not 24), St Gabriel of Our Lady of Sorrows on 28 February (not 27), and + the sixth kalends of March is said TWICE -- "bis dicitur sexto + calendas... die 24 et die 25". That last clause names the MECHANISM, not + two independent exceptions: the Roman calendar's intercalary day is + inserted by DOUBLING the sixth kalends (civil 24 February in a common + year), not by appending a 29th day at the month's end. Reckoned by + kalends position: 24 Feb = VI Kal. Mart., 25 Feb = V Kal., 26 Feb = IV + Kal., 27 Feb = III Kal., 28 Feb = pridie Kal. In a leap year VI Kal. + itself falls on TWO consecutive civil days (24th and 25th, "bis"), and + every kalends position after it is pushed one civil day later as a + result: V Kal. from 25th to 26th, IV Kal. from 26th to 27th, III Kal. + (Gabriel) from 27th to 28th, pridie Kal. from 28th to 29th. A feast fixed + at VI Kal. itself (Matthias) is kept on the SECOND occurrence, not the + first -- 25 February carries it, 24 February carries no fixed office at + all that year (confirmed against the LMS Ordo witness, + data/ef/expected-divergences-lms.sexp entry L3: 24 February 2024 is + titled plainly "EMBER SATURDAY of LENT", no Matthias anywhere near it). + + IMPLEMENTED AS THE GENERAL MECHANISM, not as "shift these two named + feasts": only three sanctoral entries exist in 23-29 February on shipped + data (peter-damien the 23rd, before the doubled kalends and therefore + unaffected; matthias the 24th; gabriel-of-our-lady-of-sorrows the 27th), + so "shift the two named feasts" and "shift every fixed entry from 24 + February" are indistinguishable on universal data -- they produce + identical output. They differ only for a locally-supplied entry, e.g. an + [--overlay] patronal feast fixed at 26 February: under the mechanism + reading it shifts to 27 February in a leap year (IV Kal. -> the civil day + IV Kal. falls on that year), exactly as a diocesan calendar compiled + against the same kalends convention would expect. The rubric's own text + states a MECHANISM ("bis dicitur sexto calendas"), not a closed list of + two saints, and this project has already been bitten once by a rule + implemented against the shipped data's coincidental shape rather than the + rubric itself (RG 16(a), CLAUDE.md's own carried lesson) -- so the general + reading is the one implemented here. + + Threaded through {!Rite.t}'s [fixed_key] field, read only by + {!Colitur_kernel.Layer.on_date}'s FIXED half: the kernel stays + rite-agnostic (a Byzantine or other non-Roman rite supplies nothing and + is unaffected), and the MOVABLE half ({!Date_spec.Easter_offset}, + {!Date_spec.Nth_weekday}) is untouched -- nothing in the footnote + concerns Easter-relative dates. *) +let bissextile_fixed_key (d : Date.t) : (int * int) option = + let m = Date.month d and day = Date.day d in + if m = 2 && Date.is_leap (Date.year d) then + if day = 24 then None (* the FIRST VI Kal.: no fixed entry lands here in a leap year *) + else if day >= 25 && day <= 29 then Some (2, day - 1) (* the SECOND VI Kal. onward, one day later *) + else Some (m, day) + else Some (m, day) + (* Compile-time check that this module satisfies the kernel's rite contract. *) module _ : Colitur_kernel.Temporal.RITE = struct let id = id diff --git a/lib/rites/rite_ef/temporal_ef.mli b/lib/rites/rite_ef/temporal_ef.mli index 5e85111..2bed5b6 100644 --- a/lib/rites/rite_ef/temporal_ef.mli +++ b/lib/rites/rite_ef/temporal_ef.mli @@ -51,6 +51,17 @@ val week : Date.t -> int option (** The lectionary key for a Sunday, or [None] if [d] is not a Sunday. *) val sunday_slug : Date.t -> string option +(** The calendarium's own bissextile (leap-year) footnote, February + (docs/research/LT.txt:5011-5014): in a leap year the sixth kalends of + March (24 February) is doubled rather than a 29th day appended, so every + fixed entry from 24 through 28 February is kept one civil day later than + usual (Matthias 24->25, Gabriel of Our Lady of Sorrows 27->28), and 24 + February itself carries no fixed office that year. Supplied as {!Rite.t}'s + [fixed_key] field -- see that field's own doc comment and this function's + definition for the full citation and the general-mechanism-vs-two-named- + feasts reasoning. *) +val bissextile_fixed_key : Date.t -> (int * int) option + val id : string (** Total over 1583..9999: every date yields exactly one temporal identity. *) -- cgit v1.3