Re: terminology/necessity of hydra:required

On 2/5/14 12:56 PM, Ruben Verborgh wrote:
> Hi Markus,
>
>>> If there is a necessity, shouldn't we split them into:
>>> - hydra:requiredProperty with domain hydra:SupportedProperty?
>>> - hydra:requiredMapping with domain hydra:IriTemplateMapping?
>> What would be the advantage of doing so?
> Required properties and required mappings are different things;
> even though they both happen to start with "required".
> Basically, the same reason that all properties are not called "hydra:has"
> (even though this example is more detailed).
>
> Having a property that doesn't have a strict range
> makes me always wonder how well-defined it is.
>
> Another way round would be:
> is there any meaningful superclass shared by SupportedProperty and IriTemplateMapping?
>
>> Hmm... I'm not sure I like this. It certainly looks weird when you look at
>> it from a class' perspective (using singulars to better illustrate the
>> difference):
>>
>>   foaf:Person hydra:supportedProperty [
>>     hydra:property foaf:name .
>>     hydra:required true .
>>   ] .
>>
>> vs.
>>
>>   foaf:Person hydra:parameter [
>>     hydra:controls foaf:name .
>>     hydra:required true .
>>   ] .
>>
>>
>> Personally, I find the first much clearer.
> Yes and no… in the first you have the confusion that a SupportedProperty is not a Property;
> the hydra:SupportedProperty is the blank node; the hydra:property is foaf:name.
>
> hydra:Parameter and hydra:controls might not be the right names though.
>
>> foaf:Person hydra:requiredParameter [
>>     hydra:property foaf:name .
>>     hydra:required true .
>>   ] .
> So a parameter would be a property that receives a value.
> That seems clearer than a SupportedProperty which is not a property.
>
> Best,
>
> Ruben
>
>

Tip:

Please don't forget to use the following to capture good descriptions in 
prose, for each property definition:

1. rdfs:label -- short label (call on skos:prefLabel in conjuction with 
rdfs:label when natural language intuitions call for many labels etc.)
2. rdfs:comment -- the kind of thing you are discussing above re. what a 
property URI actually denotes and its intended relation semantics
3. dcterms:description -- if there's much more that can be placed in a 
comment i.e., you need the comment plus a more detailed description in prose
4. foaf:depiction -- not a regular pattern today, but will become more 
popular over time, since a picture always speaks a thousand words.

I use this approach in my Glossary of Terms document [1].

[1] http://bit.ly/19NRwnB -- Glossary of Terms.

-- 

Regards,

Kingsley Idehen	
Founder & CEO
OpenLink Software
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