[tei-council] Dates and calendars

[Martin Holmes]

Hi all,

I've just been working on date/calendar issues, and I've come up against 
what looks like rather an anomaly. Our default values for @when etc. are 
this:

data.temporal.w3c =
    xsd:date
  | xsd:gYear
  | xsd:gMonth
  | xsd:gDay
  | xsd:gYearMonth
  | xsd:gMonthDay
  | xsd:time
  | xsd:dateTime

So I went to the W3C site to find out about calendar issues, and I 
discovered this:

"The ·primitive· datatypes duration, dateTime, time, date, gYearMonth, 
gMonthDay, gDay, gMonth and gYear use lexical formats inspired by [ISO 
8601]... [ISO 8601] "specifies the representation of dates in the 
proleptic Gregorian calendar and times and representations of periods of 
time". The proleptic Gregorian calendar includes dates prior to 1582 
(the year it came into use as an ecclesiastical calendar).

[...]

"gYearMonth represents a specific gregorian month in a specific 
gregorian year."

[...]

"gYear represents a gregorian calendar year."

<http://www.w3.org/TR/xmlschema-2/#date>

So what on earth are we doing when we encode something like this?

<date when="1424-02" calendar="#julian"/>

The XSD specification for @when insists that it's Gregorian, yet our 
@calendar says something different.

This is problematic, surely?

Cheers,
Martin

-- 
Martin Holmes
University of Victoria Humanities Computing and Media Centre
(mholmes at uvic.ca)