- From: simon via GitHub <sysbot+gh@w3.org>
- Date: Thu, 22 Jun 2017 05:18:59 +0000
- To: public-poe-archives@w3.org
@vroddon
> About allowing: `<http://example.com/policy:01> odrl:permission odrl:present`
>**Pros:**
>
> + A policy can be described as a resource (policy01) with a set of properties and values.
well technically, the same holds true for:
```turtle
<http://example.com/policy:01>
a odrl:Policy ;
odrl:permission [
a odrl:Permission ;
odrl:action odrl:present ;
odrl:assignee ex:Bob ;
odrl:target ex:Asset1 ;
] .
```
where `<http://example.com/policy:01>` is also a resource with properties and values ;)
> ... Ideal for lazy implementors, **easy storage/processing** (a policy as a POJO, stored in a single table in a relational database, or in a couple of columns in a CSV file).
> + **Easy understandability**, "less lines in a powerpoint": nobody will be able to say "I dont understand simple ODRL policies". Developers of the world happy.
There's an important difference between making policies _"easy to understand"_ or _"easy to store/process"_.
As outlined [here](https://www.w3.org/2016/poe/wiki/Policy_Inference) and here [2.7 Policy Rule Composition](https://w3c.github.io/poe/model/#composition), a user can write compact (thus easy to comprehend) policies, but in order to achieve interoperability an ODRL processor has to derive the policy's expanded/atomic form. If the same processor has to process a "normal" ODRL policy, it simply skips the expansion part, but is otherwise able to proceed as usual.
However, if you skip the expansion/transformation step and work with the compact representation only, you will indeed have "less lines in a ppt", but loose expressiveness and interoperability with "normal" policies.
---------------
@nitmws
> We at IPTC have a rule for the syntax design: **don't support expressing the same semantic assertion by syntax variants differently.** The reason is quite simple: a parser has to check all syntax variants before statements can be retrieved from a document - and this makes parsers more complex and expensive.
With that background I don't support such shortcuts - what is the real benefit?
What's your take on [2.7 Policy Rule Composition](https://w3c.github.io/poe/model/#composition) then?
--
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Received on Thursday, 22 June 2017 05:19:05 UTC