%%%----------------------------------------------------------------------------
-module(hope_kv_list).
--behavior(hope_dictionary).
+-include_lib("hope_kv_list.hrl").
+
+-behavior(hope_gen_dictionary).
-export_type(
[ t/2
-export(
[ empty/0
, get/2
+ , get/3
, set/3
, update/3
, pop/2
, fold/3
, of_kv_list/1
, to_kv_list/1
+ , find_unique_presence_violations/2 % No optional keys
+ , find_unique_presence_violations/3 % Specify optional keys
+ , validate_unique_presence/2 % No optional keys
+ , validate_unique_presence/3 % Specify optional keys
]).
-type t(K, V) ::
[{K, V}].
+-type presence_violations(A) ::
+ % This is a hack to effectively parametarize the types of record fields.
+ % IMPORTANT: Make sure that the order of fields matches the definition of
+ % #hope_kv_list_presence_violations
+ { hope_kv_list_presence_violations
+ , [A] % keys_missing
+ , [A] % keys_duplicated
+ , [A] % keys_unsupported
+ }.
+
+-type presence_error(A) ::
+ {keys_missing , [A]}
+ | {keys_duplicated , [A]}
+ | {keys_unsupported , [A]}
+ .
+
%% ============================================================================
%% API
; {K, V} -> {some, V}
end.
+-spec get(t(K, V), K, V) ->
+ V.
+get(T, K, Default) ->
+ Vopt = get(T, K),
+ hope_option:get(Vopt, Default).
+
-spec set(t(K, V), K, V) ->
t(K, V).
set(T, K, V) ->
% TODO: Decide if validation is to be done here. Do so if yes.
List.
+-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
+ }.
+
%% ============================================================================
%% Helpers