Is it required to explicitly state that a JSON array might be empty?

[alejandro-perez]

oidcfederation/draft/oidcfed.hf.txt

Lines 253 to 254 in 3a6c54a

	of entities that is further up in the trust chain. The array may
	be an empty list. The JSON array can be used to simplify the

[rohe]

What's missing is the interpretation of the array being empty compared to not being empty.
In my view we should have a binary interpretation of what's in the array:

If it is empty, it means that the issuer of the entity statement has no idea which trust anchors can be found if you follow that authority_hint.
If the the array is not empty then the list of entity IDs should be exhaustive. It MUST contain all the trust anchors you can find following that authority_hint.

If it can be a subset, then it's close to useless.