+-spec validate_unique_presence(t(K, _V), [K]) ->
+ hope_result:t(ok, [presence_error(K)]).
+validate_unique_presence(T, KeysRequired) ->
+ KeysOptional = [],
+ validate_unique_presence(T, KeysRequired, KeysOptional).
+
+-spec validate_unique_presence(t(K, _V), [K], [K]) ->
+ hope_result:t(ok, [presence_error(K)]).
+validate_unique_presence(T, KeysRequired, KeysOptional) ->
+ case find_unique_presence_violations(T, KeysRequired, KeysOptional)
+ of #hope_kv_list_presence_violations
+ { keys_missing = []
+ , keys_duplicated = []
+ , keys_unsupported = []
+ } ->
+ {ok, ok}
+ ; #hope_kv_list_presence_violations
+ { keys_missing = KeysMissing
+ , keys_duplicated = KeysDuplicated
+ , keys_unsupported = KeysUnsupported
+ } ->
+ ErrorMissing =
+ case KeysMissing
+ of [] -> []
+ ; [_|_] -> [{keys_missing, KeysMissing}]
+ end,
+ ErrorDups =
+ case KeysDuplicated
+ of [] -> []
+ ; [_|_] -> [{keys_duplicated, KeysDuplicated}]
+ end,
+ ErrorUnsupported =
+ case KeysUnsupported
+ of [] -> []
+ ; [_|_] -> [{keys_unsupported, KeysUnsupported}]
+ end,
+ Errors = ErrorDups ++ ErrorMissing ++ ErrorUnsupported,
+ {error, Errors}
+ 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) ->
+ KeysSupported = KeysRequired ++ KeysOptional,
+ KeysGiven = [K || {K, _V} <- T],
+ KeysGivenUnique = lists:usort(KeysGiven),
+ KeysDuplicated = lists:usort(KeysGiven -- KeysGivenUnique),
+ KeysMissing = KeysRequired -- KeysGivenUnique,
+ KeysUnsupported = KeysGivenUnique -- KeysSupported,
+ #hope_kv_list_presence_violations
+ { keys_missing = KeysMissing
+ , keys_duplicated = KeysDuplicated
+ , keys_unsupported = KeysUnsupported
+ }.
+