diff --git a/src/hamt_dict.erl b/src/hamt_dict.erl new file mode 100644 index 0000000..1c38d9b --- /dev/null +++ b/src/hamt_dict.erl @@ -0,0 +1,139 @@ +%% -*- coding: utf-8 -*- +%% +%% %CopyrightBegin% +%% +%% Copyright (C) 2013 Gregory Burd. All Rights Reserved. +%% +%% The contents of this file are subject to the Mozilla Public License, +%% Version 2, (the "License"); you may not use this file except in +%% compliance with the License. You should have received a copy of the +%% Mozilla Public License along with this software. If not, it can be +%% retrieved online at http://www.mozilla.org/MPL/ +%% +%% Software distributed under the License is distributed on an "AS IS" +%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See +%% the License for the specific language governing rights and limitations +%% under the License. +%% +%% %CopyrightEnd% +-module(hamt_dict). +-author('Steve Vinoski '). + +-export([append/3, append_list/3, erase/2, fetch/2, + fetch_keys/1, filter/2, find/2, fold/3, + from_list/1, is_key/2, map/2, merge/3, + new/0, size/1, store/3, to_list/1, + update/3, update/4, update_counter/3]). + +append(Key, Value, Dict) -> + NewVal = case hamt:get(Key, Dict) of + {error, not_found} -> + [Value]; + OldVal -> + OldVal ++ [Value] + end, + hamt:put(Key, NewVal, Dict). + +append_list(Key, ValList, Dict) when is_list(ValList) -> + NewVal = case hamt:get(Key, Dict) of + {error, not_found} -> + ValList; + OldVal when is_list(OldVal) -> + OldVal ++ ValList; + _ -> + error(badarg) + end, + hamt:put(Key, NewVal, Dict). + +erase(Key, Dict) -> + hamt:delete(Key, Dict). + +fetch(Key, Dict) -> + case hamt:get(Key, Dict) of + {error, not_found} -> + error(badarg); + Value -> + Value + end. + +fetch_keys(Dict) -> + hamt:fold(fun(Key, _, Acc) -> [Key|Acc] end, Dict, []). + +filter(Pred, Dict) -> + Fold = fun(Key, Value, Acc) -> + case Pred(Key, Value) of + true -> + hamt:put(Key, Value, Acc); + _ -> + Acc + end + end, + hamt:fold(Fold, Dict, hamt:new()). + +find(Key, Dict) -> + case hamt:get(Key, Dict) of + {error, not_found} -> + error; + Value -> + {ok, Value} + end. + +fold(Fun, Acc0, Dict) -> + hamt:fold(Fun, Dict, Acc0). + +from_list(List) -> + hamt:from_list(List). + +is_key(Key, Dict) -> + case hamt:get(Key, Dict) of + {error, not_found} -> + false; + _ -> + true + end. + +map(Fun, Dict) -> + hamt:map(Fun, Dict). + +merge(Fun, Dict1, Dict2) -> + hamt:fold(fun(Key, Val1, Dict) -> + update(Key, fun(Val2) -> Fun(Key, Val1, Val2) end, Val1, Dict) + end, Dict2, Dict1). + +new() -> + hamt:new(). + +size(Dict) -> + hamt:fold(fun(_, _, Acc) -> Acc+1 end, Dict, 0). + +store(Key, Value, Dict) -> + hamt:put(Key, Value, Dict). + +to_list(Dict) -> + hamt:to_list(Dict). + +update(Key, Fun, Dict) -> + case hamt:get(Key, Dict) of + {error, not_found} -> + error(badarg); + Value -> + hamt:put(Key, Fun(Value), Dict) + end. + +update(Key, Fun, Initial, Dict) -> + NewVal = case hamt:get(Key, Dict) of + {error, not_found} -> + Initial; + Value -> + Fun(Value) + end, + hamt:put(Key, NewVal, Dict). + +update_counter(Key, Increment, Dict) -> + NewVal = case hamt:get(Key, Dict) of + {error, not_found} -> + Increment; + Value -> + Value+Increment + end, + hamt:put(Key, NewVal, Dict).