; data/of/amendments/006-mary-mother-of-the-church.sexp -- ADDS the
; Blessed Virgin Mary, Mother of the Church, to the General Roman
; Calendar. The one genuinely MOVABLE amendment in this inventory.
;
; Decree: Congregation for Divine Worship and the Discipline of the
; Sacraments, 11 February 2018, Prot. N. 1037/2017. Signed Robertus Card.
; Sarah (Praefectus) + Arturus Roche (Archiepiscopus a Secretis).
; Published: AAS 110 (2018), 437-438 (decree text continues past 438;
; index cites 437 as the start page).
;
; What it does, verified directly against the decree's own operative
; sentence (docs/research/of/aas-monthly/2018_marzo.pdf, line 2434-2437 of
; the extracted transcript): "Summus autem Pontifex Franciscus... decrevit
; ut memoriam B. Mariae Virginis, Ecclesiae Matris, in Calendarium
; Romanum inscribendam esse Feria II post Pentecosten et quotannis
; celebrandam" -- inscribes a MEMORIA (obligatory: no "ad libitum"
; qualifier anywhere in the operative sentence) on "Feria II post
; Pentecosten", the MONDAY AFTER PENTECOST.
;
; Date arithmetic, verified rather than trusted: Pentecost is Easter+49
; (the 50th day of the Paschal season inclusive of Easter itself), so the
; following Monday is Easter+50. Date_spec.Easter_offset 50 is exactly
; this; kernel-level and rite-agnostic (built for EF's Rogation
; Wednesday), no code change needed. See test_amendments_of.ml's own
; test_mater_ecclesiae_monday_after_pentecost, which re-derives the
; calendar date from Colitur_kernel.Computus.gregorian_easter in three
; real years rather than trusting this offset's own arithmetic.
;
; The day carries no other GRC celebration to displace on any FIXED date
; -- but the decree's own destination is a MOVABLE one, so this is not
; quite true every year: see the finding recorded below.
;
; `la` name taken directly from the decree's own text ("B. Mariae
; Virginis, Ecclesiae Matris", expanded here to "Beatae Mariae Virginis,
; Ecclesiae Matris" to match calendar-2002.sexp's own convention of
; writing out abbreviations in `la` names); `en` is this task's own
; translation (no lectio entry exists for this decree -- it postdates
; lectio's own last GRC sync).
;
; *** FINDING, worth surfacing rather than silently shipping: a real,
; unresolved Precedence_of interaction. *** Easter+50 ranges over 11 May
; - 14 June across the Gregorian Easter window (22 March - 25 April).
; Several FIXED Memoria_obligatoria entries already sit inside that
; window in data/of/calendar-2002.sexp: 26 May (Philip Neri), 1 June
; (Justin Martyr), 3 June (Charles Lwanga & companions), 5 June
; (Boniface), 11 June (Barnabas), 13 June (Anthony of Padua). Verified
; computationally (Meeus/Jones/Butcher Gregorian Easter, 1583-2100) that
; Easter+50 DOES land on each of those dates in real years -- e.g. 2011
; (Easter 24 April) puts Mary, Mother of the Church squarely on 13 June,
; Anthony of Padua's own day. On such a year both candidates band at
; Tabula III.10 (100, both universal Memoria_obligatoria), a genuine tie
; Precedence_of.band does not and cannot break: Precedence.resolve's own
; tie-break (Slug.compare) then picks whichever slug sorts first
; alphabetically as the sole OBSERVED day, silently omitting the other
; for that year -- not a crash, not a diagnostic, just a deterministic
; but liturgically arbitrary pick. Normae universales n. 14's own text
; (docs/research/of/normae-universales-2002-transcription.md) resolves the
; AD-LIBITUM/AD-LIBITUM case explicitly ("una tantum celebrari potest,
; omissis ceteris") but is silent on two OBLIGATORY memorials colliding;
; pastoral practice generally reduces both to ad libitum for that one
; year, which Precedence_of.ml implements nowhere. Recorded here as a
; real, load-bearing gap -- not fixed, out of this data-only task's own
; scope, and not unique to this entry (any future obligatory-memorial
; overlay entry on a fixed May/June date has the identical exposure).
((id of-amend-06-mary-mother-of-the-church)
  (directives
    ((Add
       ((date (Easter_offset 50))
         (cel
           ((slug mary-mother-of-the-church)
             (names
               ((en "The Blessed Virgin Mary, Mother of the Church")
                (la "Beatae Mariae Virginis, Ecclesiae Matris")))
             (rank Memoria_obligatoria) (status Feast) (colour White)
             (subject Bvm) (citations ()) (layer of-universal)))))
     )))