type Replacement = record { expected: list<string>; targets: list<atom-ref<Node>>; };
external atom Node id "collection:node";
interface NodeData id "collection:data" revision "collection:data@1" {
  queryable portable value version id "collection:version" : list<string> {
    get id "collection:version:get" execution snapshot;
  }
  operation replace id "collection:replace" : Replacement -> unit {
    call id "collection:replace:call" execution transaction;
  }
  operation ensure id "collection:ensure" : unit -> atom-ref<Node> {
    call id "collection:ensure:call" execution transaction;
  }
  queryable value label id "collection:label" : string {
    get id "collection:label:get" execution snapshot;
    set id "collection:label:set" execution transaction;
  }
  queryable relation items id "collection:items" : many atom Node {
    resolve id "collection:items:resolve" execution snapshot;
  }
  queryable relation containers id "collection:containers" : many atom Node {
    resolve id "collection:containers:resolve" execution snapshot;
  }
  queryable relation detail id "collection:detail" : optional-one atom Node {
    resolve id "collection:detail:resolve" execution snapshot;
  }
}