SODA, half-client and remaining gripe collection

[Mark Taylor]

On Mon, 11 Apr 2016, Markus Demleitner wrote:

> Hi all,
> 
> On Mon, Apr 11, 2016 at 11:56:16AM +0100, Mark Taylor wrote:
> > On Tue, 29 Mar 2016, Markus Demleitner wrote:
> > 
> > > (6) @value="" universally valid
> > > 
> > > VOTable 1.3 says "If the TD element is empty (<TD/> or <TD></TD>) the
> > > cell is considered to contain no data, i.e. to be null."  Since we're
> > > saying "parse PARAM/@value like you parse TABLEDATA cells" (I really
> > > think VOTable itself should say this in sect. 4.1, last bullet point), I
> > > *think* we're fine saying "Generate your UI from all the PARAMs that
> > > have value="" (which, in effect, we're doing right now and we'd
> > > certainly be doing if we adopt (5).  I'd much prefer if that were made
> > > explicit somewhere.  Bug me for a doc patch if everyone interested agrees.
> > 
> > It is probably true that VOTable ought to specify this.
> > However, it's not too surprising that it doesn't.
> 
> Uh -- I think the question of PARAM/@value literals is independent of
> this particular use, and I'd still suggest VOTable should say "These
> values are encoded as if it were TABLEDATA cells." and then perhaps
> something as to whether or not VALUES/@null is to be evaluated.

I'm not disagreeing.

> Nothing I can make out in the current VOTable spec says that much,
> and I strongly suspect that if we looked at current implementations,
> not many actually work like this (and consequently probably fail as
> soon as we have array-typed PARAMs).

Can't speak for others, but STIL interprets empty-string PARAM/@value
attributes as null values, and works fine with array-valued PARAMs
(using space-separated values as for TDs).

--
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/