first/next implementations for hanoidb

to_ulf.erl

-module(to_ulf).

-include_lib("hanoidb/include/hanoidb.hrl").

first(Ref) ->
    case hanoidb:fold_range(Ref,fun(K,V,Acc) -> [{K,V}|Acc] end,[],
                    #key_range{from_key= <<>>, limit=1, to_key=undefined})
    of
        [] -> '$end_of_table';
        [{Key,Value}] -> {Key,Value}
    end.

next(Ref, Key) when is_binary(Key) ->
    case hanoidb:fold_range(Ref,fun(K,V,Acc) -> [{K,V}|Acc] end,[],
                             #key_range{from_key=Key, from_inclusive=false, limit=1, to_key=undefined})
    of
        [] -> '$end_of_table';
        [{Key,Value}] -> {Key,Value}
    end.