ADQL 2.1 and geometry language features

[Mark Taylor]

Dear ADQL authors/editors,

I have encountered what I believe is an inconsistency in the most
recent ADQL 2.1 document (PR-ADQL-2.1-20180112).

The geometric functions CIRCLE, CONTAINS, DISTANCE etc are labelled
with the feature type

   ivo://ivoa.net/std/TAPRegExt#features-adql-geo

However, in ADQL 2.0, the corresponding functionality was marked
by the feature (defined in TAPRegExt 1.0):

   ivo://ivoa.net/std/TAPRegExt#features-adqlgeo

(no second hyphen)

I think the ADQL 2.1 text has to be amended for backward compatibility.
It means that the ADQL 2.1 features won't all have the same form
(the other new ones are all look like
ivo://ivoa.net/std/TAPRegExt#features-adql-*), but that's too bad.

[I considered noting this as an Issue at https://github.com/ivoa-std/ADQL
but since nobody else has entered an issue so far, I didn't.
But I can add it there on request.]

Mark

--
Mark Taylor   Astronomical Programmer   Physics, Bristol University, UK
m.b.taylor at bris.ac.uk +44-117-9288776  http://www.star.bris.ac.uk/~mbt/