+ case find_unique_presence_violations(T, KeysRequired, KeysOptional)
+ of #hope_kv_list_presence_violations
+ { keys_missing = []
+ , keys_duplicated = []
+ , keys_unsupported = []
+ } ->
+ {ok, T}
+ ; #hope_kv_list_presence_violations{}=Violations ->
+ {error, presence_violations_to_list(Violations)}
+ end.
+
+-spec find_unique_presence_violations(t(K, _V), [K]) ->
+ presence_violations(K).
+find_unique_presence_violations(T, KeysRequired) ->
+ KeysOptional = [],
+ find_unique_presence_violations(T, KeysRequired, KeysOptional).
+
+-spec find_unique_presence_violations(t(K, _V), [K], [K]) ->
+ presence_violations(K).
+find_unique_presence_violations(T, KeysRequired, KeysOptional) ->