-module(embeds@internal).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([traverse_map/2, 'try'/2]).

-spec do_traverse_map(
    list(INQ),
    fun((INQ) -> {ok, INS} | {error, list(INT)}),
    list(INS),
    list(INT)
) -> {ok, list(INS)} | {error, list(INT)}.
do_traverse_map(List, Body, Oks, Errs) ->
    case List of
        [] ->
            case Errs of
                [] ->
                    {ok, lists:reverse(Oks)};

                _ ->
                    {error, lists:reverse(Errs)}
            end;

        [Head | Tail] ->
            case Body(Head) of
                {ok, Ok} ->
                    do_traverse_map(Tail, Body, [Ok | Oks], Errs);

                {error, Err} ->
                    do_traverse_map(Tail, Body, Oks, lists:append(Err, Errs))
            end
    end.

-spec traverse_map(list(INF), fun((INF) -> {ok, INH} | {error, list(INI)})) -> {ok,
        list(INH)} |
    {error, list(INI)}.
traverse_map(List, Body) ->
    do_traverse_map(List, Body, [], []).

-spec 'try'(
    {ok, IOD} | {error, IOE},
    fun((IOD) -> {ok, IOH} | {error, list(IOE)})
) -> {ok, IOH} | {error, list(IOE)}.
'try'(Result, F) ->
    case Result of
        {ok, Ok} ->
            F(Ok);

        {error, Err} ->
            {error, [Err]}
    end.