VOEvent - Param comment

[Alasdair Allan]

Ray Plante wrote:
> Petr Kubanek wrote:
>> You are making in my point-of-view classical XML-designers mistake.
>
> While your suggestion certainly has advantages, the best choice is not
> obvious.
>
>> <Param name="TRIGGER_NUM" value="114299" ucd="meta.id" />
>> <Param name="RATE_SIGNIF" value="20.49"  ucd="stat.snr" />
>> <Param name="GRB_INTEN  " value="73288"  ucd="phot.count" />
>>
>> Let's have something like:
>>
>> <GRB>
>>   <trigger_num>114299</trigger_num>
>>   <rate_signif>20.49</rate_signif>
>>   <grb_inten>73288</grb_intent>
>> </GRB>

This doesn't meet the design goals, see below...

> The difference here is between what I call a generic container and a
> semantic container.  The latter is helpful when the scope of  
> meaning is
> well contained.

The later is useful if you know the contents the message will carry,  
the <Param> element was designed the way it was precisely because we  
have absolutely no idea the semantic content that the message will  
have to carry. If you look at, for instance, OGLE and GCN messages,  
the <Param> elements carry totally different things. That's why it  
has a ucd="" attribute to provide the semantic meaning that you seem  
to want.

Al.