"@container": "@annotation"

[Tpt]

Thank you for this work on JSON-LD-star. It's great to see it coming forward!

I encountered multiple datasources where an attribute I would like to parse as an RDF* annotation is in the same level as the other attributes of the triple object.

For example I would like to be able to parse "role" into an annotation of the "actor" relation from the following JSON:

{
   "name": "My movie",
   "actor": {
        "name": "John Doe",
        "role": "the vilain"
   }
}

for that, allowing something like "@container": "@annotation" in the context might be convenient.

To follow the example, it might be very handy to write a context like:

{
   "@vocab": "http://schema.org/",
   "actor": {"@type": "Person"},
   "role": {"@container": "@annotation"}
}

To get the following RDF*:

@prefix schema: <http://schema.org/>

_:a schema:name "My movie" .
_:a schema:actor _:b .
<< _:a schema:actor _:b . >> schema:role "the vilain" .
_b: a schema:Actor .
_b: schema:name "John Doe" .

What do you think about it?

[pchampin]

@Tpt if you have any reference to such formats, we would be interested (to document the existing use-cases).

If this is a common practice, I agree that we should address it.
I sympathize with the will to reuse an existing mechanism, but I am not entirely sure about @container for this. The general effect of container is to alter the value of the property, by wrapping it (e.g. @list, @graph) or unwrapping it (language-map, id-map, and other *-maps). What you suggest here is to wrap the property and the value into something that is added to the parent object.
This is just a gut-feeling, I'm not either strongly against it.

Possible alternative: use "@annotation": true in the term definition?

[Tpt]

@Tpt if you have any reference to such formats, we would be interested (to document the existing use-cases).

It's a great question. I don't have any good example of public formats doing that. My example is taken from a proprietary one.

[gkellogg]

It could be a question of what creates the least intellectual load; @container: @annotation might be clear. Adding a new @annotation: true to a term definition does clarify its use.

Either could allow the use within a value object, which otherwise could not contain any other properties.

(It would be nice if a conversation could be turned into an issue, as there are too many places to remember to look as it is).