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Diffstat (limited to 'lib/stdlib/src/maps.erl')
| -rw-r--r-- | lib/stdlib/src/maps.erl | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/lib/stdlib/src/maps.erl b/lib/stdlib/src/maps.erl new file mode 100644 index 0000000000..4ef1638e6d --- /dev/null +++ b/lib/stdlib/src/maps.erl @@ -0,0 +1,203 @@ +%% +%% %CopyrightBegin% +%% +%% Copyright Ericsson AB 2013. All Rights Reserved. +%% +%% The contents of this file are subject to the Erlang Public License, +%% Version 1.1, (the "License"); you may not use this file except in +%% compliance with the License. You should have received a copy of the +%% Erlang Public License along with this software. If not, it can be +%% retrieved online at http://www.erlang.org/. +%% +%% 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(maps). + +-export([ + fold/3, + map/2, + size/1, + without/2, + get/3 + ]). + + +%%% BIFs +-export([ + get/2, + find/2, + from_list/1, + is_key/2, + keys/1, + merge/2, + new/0, + put/3, + remove/2, + to_list/1, + update/3, + values/1 + ]). + +-spec get(Key,Map) -> Value when + Key :: term(), + Map :: map(), + Value :: term(). + +get(_,_) -> erlang:nif_error(undef). + + +-spec find(Key,Map) -> {ok, Value} | error when + Key :: term(), + Map :: map(), + Value :: term(). + +find(_,_) -> erlang:nif_error(undef). + + +-spec from_list(List) -> Map when + List :: [{Key,Value}], + Key :: term(), + Value :: term(), + Map :: map(). + +from_list(_) -> erlang:nif_error(undef). + + +-spec is_key(Key,Map) -> boolean() when + Key :: term(), + Map :: map(). + +is_key(_,_) -> erlang:nif_error(undef). + + +-spec keys(Map) -> Keys when + Map :: map(), + Keys :: [Key], + Key :: term(). + +keys(_) -> erlang:nif_error(undef). + + +-spec merge(Map1,Map2) -> Map3 when + Map1 :: map(), + Map2 :: map(), + Map3 :: map(). + +merge(_,_) -> erlang:nif_error(undef). + + + +-spec new() -> Map when + Map :: map(). + +new() -> erlang:nif_error(undef). + + +-spec put(Key,Value,Map1) -> Map2 when + Key :: term(), + Value :: term(), + Map1 :: map(), + Map2 :: map(). + +put(_,_,_) -> erlang:nif_error(undef). + + +-spec remove(Key,Map1) -> Map2 when + Key :: term(), + Map1 :: map(), + Map2 :: map(). + +remove(_,_) -> erlang:nif_error(undef). + + +-spec to_list(Map) -> [{Key,Value}] when + Map :: map(), + Key :: term(), + Value :: term(). + +to_list(_) -> erlang:nif_error(undef). + + +-spec update(Key,Value,Map1) -> Map2 when + Key :: term(), + Value :: term(), + Map1 :: map(), + Map2 :: map(). + +update(_,_,_) -> erlang:nif_error(undef). + + +-spec values(Map) -> Keys when + Map :: map(), + Keys :: [Key], + Key :: term(). + +values(_) -> erlang:nif_error(undef). + + +%%% End of BIFs + +-spec get(Key, Map, Default) -> Value | Default when + Key :: term(), + Map :: map(), + Value :: term(), + Default :: term(). + +get(Key, Map, Default) -> + case maps:find(Key, Map) of + {ok, Value} -> + Value; + error -> + Default + end. + + +-spec fold(Fun,Init,Map) -> Acc when + Fun :: fun((K, V, AccIn) -> AccOut), + Init :: term(), + Acc :: term(), + AccIn :: term(), + AccOut :: term(), + Map :: map(), + K :: term(), + V :: term(). + +fold(Fun, Init, Map) when is_function(Fun,3), is_map(Map) -> + lists:foldl(fun({K,V},A) -> Fun(K,V,A) end,Init,maps:to_list(Map)). + +-spec map(Fun,Map1) -> Map2 when + Fun :: fun((K, V1) -> V2), + Map1 :: map(), + Map2 :: map(), + K :: term(), + V1 :: term(), + V2 :: term(). + +map(Fun, Map) when is_function(Fun, 2), is_map(Map) -> + maps:from_list(lists:map(fun + ({K,V}) -> + {K,Fun(K,V)} + end,maps:to_list(Map))). + + +-spec size(Map) -> non_neg_integer() when + Map :: map(). + +size(Map) when is_map(Map) -> + erlang:map_size(Map). + + +-spec without(Ks,Map1) -> Map2 when + Ks :: [K], + Map1 :: map(), + Map2 :: map(), + K :: term(). + +without(Ks, M) when is_list(Ks), is_map(M) -> + maps:from_list([{K,V}||{K,V} <- maps:to_list(M), not lists:member(K, Ks)]). |