Remove "month code" as a term

Clarifies relationship with standard tags used in the ABNF Fixes FamilySearch#570 Signed-off-by: Dave Thaler <[email protected]>
dthaler · Nov 19, 2024 · a3a727d · a3a727d
1 parent 024fc52
commit a3a727d
Showing 1 changed file with 49 additions and 47 deletions.
diff --git a/specification/gedcom-6-appendix-calendars.md b/specification/gedcom-6-appendix-calendars.md
@@ -5,34 +5,36 @@
 This specification defines 4 calendars: `GREGORIAN`, `JULIAN`, `FRENCH_R`, and `HEBREW`.
 Previous versions also provided for, but did not define the meaning of, `ROMAN` and `UNKNOWN` calendars.
 
-Extension calendars should use the usual rules for extensions, including using `_` as the leading character of the calendar name. Month codes in extension calendars must either be already used for the same month name in another calendar or must start with `_`. Only upper case characters are allowed in month codes.
+Extension calendars should use the usual rules for extensions, including using `_` as the leading character of the calendar name.
+
+All month tags must either be standard tags defined for the month name in a standard calendar or be extension tags. Only upper case characters are allowed in month tags.
 
 Each calendar must list its permitted epochs and their meaning.
 
 Each month defined in this section has a URI constructed by concatenating
-`g7:month-` to the month code;
-for example, the month of Elul has the URI `http://gedcom.io/terms/v7/month-ELL`.
+`g7:month-` to the standard tag;
+for example, the month of Elul has the standard tag `ELL` and the URI `http://gedcom.io/terms/v7/month-ELL`.
 
 ### `GREGORIAN`
 
 The Gregorian calendar is the now-ubiquitous calendar introduced by Pope Gregory XIII in 1582 to correct the Julian calendar which was slowly drifting relative to the seasons.
 
 Permitted months are
 
-|Code   |Name       |
-|:------|:----------|
-| `JAN` | January   |
-| `FEB` | February  |
-| `MAR` | March     |
-| `APR` | April     |
-| `MAY` | May       |
-| `JUN` | June      |
-| `JUL` | July      |
-| `AUG` | August    |
-| `SEP` | September |
-| `OCT` | October   |
-| `NOV` | November  |
-| `DEC` | December  |
+|`stdTag`|Name       |
+|:-------|:----------|
+| `JAN`  | January   |
+| `FEB`  | February  |
+| `MAR`  | March     |
+| `APR`  | April     |
+| `MAY`  | May       |
+| `JUN`  | June      |
+| `JUL`  | July      |
+| `AUG`  | August    |
+| `SEP`  | September |
+| `OCT`  | October   |
+| `NOV`  | November  |
+| `DEC`  | December  |
 
 The epoch marker `BCE` is permitted in this calendar;
 year *y* BCE indicates a year *y* years before year 1.
@@ -58,21 +60,21 @@ The French Republican calendar or French Revolutionary calendar are the names gi
 
 Permitted months are
 
-|Code  |Name                |
-|:-----|:-------------------|
-|`VEND`|Vendémiaire         |
-|`BRUM`|Brumaire            |
-|`FRIM`|Frimaire            |
-|`NIVO`|Nivôse              |
-|`PLUV`|Pluviôse            |
-|`VENT`|Ventôse             |
-|`GERM`|Germinal            |
-|`FLOR`|Floréal             |
-|`PRAI`|Prairial            |
-|`MESS`|Messidor            |
-|`THER`|Thermidor           |
-|`FRUC`|Fructidor           |
-|`COMP`|Jour Complémentaires|
+|`stdTag`|Name                |
+|:-------|:-------------------|
+|`VEND`  |Vendémiaire         |
+|`BRUM`  |Brumaire            |
+|`FRIM`  |Frimaire            |
+|`NIVO`  |Nivôse              |
+|`PLUV`  |Pluviôse            |
+|`VENT`  |Ventôse             |
+|`GERM`  |Germinal            |
+|`FLOR`  |Floréal             |
+|`PRAI`  |Prairial            |
+|`MESS`  |Messidor            |
+|`THER`  |Thermidor           |
+|`FRUC`  |Fructidor           |
+|`COMP`  |Jour Complémentaires|
 
 No epoch marker is permitted in this calendar.
 
@@ -82,21 +84,21 @@ The URI for this calendar is `g7:cal-FRENCH_R`
 
 The Hebrew calendar is the name given to the calendar used by Jewish peoples around the world which developed into its current form in the early ninth century. It traditionally marks new days at sunset, not midnight. Its first day (1 Tishrei 1) primarily overlapped with Gregorian 7 September 3761 BCE and Julian 7 October 3761 BCE (starting at sunset on the 6th day of those months).
 
-|Code | Name                                                   |
-|:----|:-------------------------------------------------------|
-|`TSH`| Tishrei (תִּשְׁרֵי) |
-|`CSH`| Marcheshvan (מַרְחֶשְׁוָן) or Cheshvan (חֶשְׁוָן) |
-|`KSL`| Kislev (כִּסְלֵו) |
-|`TVT`| Tevet (טֵבֵת) |
-|`SHV`| Shevat (שְׁבָט) |
-|`ADR`| Adar I, Adar Rishon, First Adar, or Adar Aleph (אדר א׳) |
-|`ADS`| Adar (אֲדָר); or Adar II, Adar Sheni, Second Adar, or Adar Bet (אדר ב׳) |
-|`NSN`| Nisan (נִיסָן) |
-|`IYR`| Iyar (אִייָר) |
-|`SVN`| Sivan (סִיוָן) |
-|`TMZ`| Tammuz (תַּמּוּז) |
-|`AAV`| Av (אָב) |
-|`ELL`| Elul (אֱלוּל) |
+|`stdTag`| Name                                                   |
+|:-------|:-------------------------------------------------------|
+|`TSH`   | Tishrei (תִּשְׁרֵי) |
+|`CSH`   | Marcheshvan (מַרְחֶשְׁוָן) or Cheshvan (חֶשְׁוָן) |
+|`KSL`   | Kislev (כִּסְלֵו) |
+|`TVT`   | Tevet (טֵבֵת) |
+|`SHV`   | Shevat (שְׁבָט) |
+|`ADR`   | Adar I, Adar Rishon, First Adar, or Adar Aleph (אדר א׳) |
+|`ADS`   | Adar (אֲדָר); or Adar II, Adar Sheni, Second Adar, or Adar Bet (אדר ב׳) |
+|`NSN`   | Nisan (נִיסָן) |
+|`IYR`   | Iyar (אִייָר) |
+|`SVN`   | Sivan (סִיוָן) |
+|`TMZ`   | Tammuz (תַּמּוּז) |
+|`AAV`   | Av (אָב) |
+|`ELL`   | Elul (אֱלוּל) |
 
 To keep the lunar-based months synchronized with the solar-based years, some years have Adar I and others do not, instead proceeding from Shevat directly to Adar II. However, in common (non-leap) years, it is common to simply write "Adar" not "Adar II", which users not aware of the distinction might incorrectly encode as `ADR` instead of `ADS`. It is recommended that systems knowing which years had Adar I and which did not replace `ADR` in common years with `ADS`.