%%
%% %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,
with/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) -> Values when
Map :: map(),
Values :: [Value],
Value :: 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)]).
-spec with(Ks, Map1) -> Map2 when
Ks :: [K],
Map1 :: map(),
Map2 :: map(),
K :: term().
with(Ks, M) when is_list(Ks), is_map(M) ->
maps:from_list([{K,V}||{K,V} <- maps:to_list(M), lists:member(K, Ks)]).
