VOTable multi-dimensional arrays too restrictive

[Mark Taylor]

On Thu, 18 Feb 2021, Markus Demleitner wrote:

> For our "list of strings" use case, a solution I could easily learn
> to like would use ASCII shift-in and shift-out, \x0e and \x0f.  For
> python
> 
>   [["ab", "c"], ["de", "fgh"]]
> 
> you'd be writing SI SI ab SO SI c SO SO SI de SO SI fgh SO SO
> -- so you could even represent arbitrarily deep nesting.  This, by
> the way, works in TABLEDATA, too; just write &#0e;, etc.  Since we
> and utf-8 don't allow control characters in char material, we might
> not even need escaping.  However, as we enter hard-core ASCII, we
> could define ESC (\x1b) as an escape character if we wanted and then
> even have SI and SO in our strings if, in some future, we want to
> make char binary-proof.

1. weird
2. neat
3. impossible, at least in TABLEDATA

Most of the ASCII control characters are not permitted in XML,
even as character entity references.  Just try to xmllint a document
containing an .  See https://www.w3.org/TR/REC-xml/#charsets.

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