solid
Deleting folders when invisible files are left
When a folder contains only .acl files, the folder listing will show up as empty. This is by design, as we do not wish to show .acl files.
However, when trying to delete the container, it will fail because the container is non-empty; yet we have no way of emptying it because we cannot see the .acl files that are there.
P: The root container's ACL can't be deleted. P: Hierarchical ACL inheritance algorithm. P: Resources come to existence prior to server advertising an associated ACL. P: The lifecycle of a resource and associated ACL (if exists) is coupled. Deleting a resource must remove associated ACL resource (not including inherited ACL). Deleting an ACL doesn't remove all resources that use that particular ACL.
C: A container can't contain any dangling ("invisible") ACLs of the resources under its containment.
Note: The view of a resource, however that is treated eg. whether acl and meta resources are to be "listed" in containment triples, or not, is both orthogonal and overruled by their own lifecycle.
Common resource delete rules apply.
