Ability to declare a container as both @index and @set

[lrowe]

I have the following indexed data structure that I'd like to preserve during compaction:

{
  "dbxref": {
    "db1": ["term1"],
    "db2": ["term2a", "term2b"]
  }
}

Declaring a context with @container: @index partly works, but I also want to preserve the array even when it has only a single member:

{
  "@context": {
    "@vocab": "http://localhost/context#",
    "dbxref": {
      "@container": "@index"
    }
  },
  "@id": "http://localhost/item1",
  "dbxref": {
    "db1": "term1",
    "db2": ["term2a", "term2b"]
  }
}

It would be helpful to have some way to declare a container as both @index and @set.

[lanthaler]

I don’t really understand what your data is supposed to mean but couldn’t you map db1 and db2 to a URI and set the containers there?

[lrowe]

The dbxref object stores links to external databases from our system indexed by database identifier. I want to avoid turning dbxref into a node in its own right (presumably necessary if the keys were to be treated as URIs) as the relationship is from the item to the external database resource, something like:

<http://localhost/item1> <rdf:seeAlso> <db1:term1> .

(We'll probably move away from this data structure, but it doesn't seem completely unreasonable.)

[lanthaler]

OK, I see. In that case the index-container is indeed the right thing. Unfortunately, there’s currently no way to use two containers at the same time.

I’ve added this issue to the JSON-LD.next milestone so that we’ll keep this in mind for the next version of JSON-LD sometime in the future. Thanks for raising this.

[gkellogg]

I propose taking this off of the 1.1 milestone; please 👍 or 👎 to favor/disfavor removing.