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-rw-r--r--lib/stdlib/doc/src/maps.xml60
-rw-r--r--lib/stdlib/src/maps.erl51
-rw-r--r--lib/stdlib/test/maps_SUITE.erl56
3 files changed, 144 insertions, 23 deletions
diff --git a/lib/stdlib/doc/src/maps.xml b/lib/stdlib/doc/src/maps.xml
index 0f58f19421..bf45461e2b 100644
--- a/lib/stdlib/doc/src/maps.xml
+++ b/lib/stdlib/doc/src/maps.xml
@@ -301,6 +301,30 @@ false</code>
</func>
<func>
+ <name name="take" arity="2"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>
+ The function removes the <c><anno>Key</anno></c>, if it exists, and its associated value from
+ <c><anno>Map1</anno></c> and returns a tuple with the removed <c><anno>Value</anno></c> and
+ the new map <c><anno>Map2</anno></c> without key <c><anno>Key</anno></c>.
+ If the key does not exist <c>error</c> is returned.
+ </p>
+ <p>
+ The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map1</anno></c> is not a map.
+ </p>
+ <p>Example:</p>
+ <code type="none">
+> Map = #{"a" => "hello", "b" => "world"}.
+#{"a" => "hello", "b" => "world"}
+> maps:take("a",Map).
+{"hello",#{"b" => "world"}}
+> maps:take("does not exist",Map).
+error</code>
+ </desc>
+ </func>
+
+ <func>
<name name="size" arity="1"/>
<fsummary></fsummary>
<desc>
@@ -357,6 +381,42 @@ false</code>
</desc>
</func>
+ <func>
+ <name name="update_with" arity="3"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Update a value in a <c><anno>Map1</anno></c> associated with <c><anno>Key</anno></c> by
+ calling <c><anno>Fun</anno></c> on the old value to get a new value. An exception
+ <c>{badkey,<anno>Key</anno>}</c> is generated if
+ <c><anno>Key</anno></c> is not present in the map.</p>
+ <p>Example:</p>
+ <code type="none">
+> Map = #{"counter" => 1},
+ Fun = fun(V) -> V + 1 end,
+ maps:update_with("counter",Fun,Map).
+#{"counter" => 2}</code>
+ </desc>
+ </func>
+
+ <func>
+ <name name="update_with" arity="4"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Update a value in a <c><anno>Map1</anno></c> associated with <c><anno>Key</anno></c> by
+ calling <c><anno>Fun</anno></c> on the old value to get a new value.
+ If <c><anno>Key</anno></c> is not present
+ in <c><anno>Map1</anno></c> then <c><anno>Init</anno></c> will be associated with
+ <c><anno>Key</anno></c>.
+ </p>
+ <p>Example:</p>
+ <code type="none">
+> Map = #{"counter" => 1},
+ Fun = fun(V) -> V + 1 end,
+ maps:update_with("new counter",Fun,42,Map).
+#{"counter" => 1,"new counter" => 42}</code>
+ </desc>
+ </func>
+
<func>
<name name="values" arity="1"/>
<fsummary></fsummary>
diff --git a/lib/stdlib/src/maps.erl b/lib/stdlib/src/maps.erl
index a52928f77f..ba9ad4f549 100644
--- a/lib/stdlib/src/maps.erl
+++ b/lib/stdlib/src/maps.erl
@@ -20,15 +20,15 @@
-module(maps).
--export([get/3,filter/2,fold/3, map/2,
- size/1,
+-export([get/3, filter/2,fold/3,
+ map/2, size/1,
+ update_with/3, update_with/4,
without/2, with/2]).
-
-%%% BIFs
+%% BIFs
-export([get/2, find/2, from_list/1,
is_key/2, keys/1, merge/2,
- new/0, put/3, remove/2,
+ new/0, put/3, remove/2, take/2,
to_list/1, update/3, values/1]).
-spec get(Key,Map) -> Value when
@@ -102,6 +102,13 @@ put(_,_,_) -> erlang:nif_error(undef).
remove(_,_) -> erlang:nif_error(undef).
+-spec take(Key,Map1) -> {Value,Map2} | error when
+ Key :: term(),
+ Map1 :: map(),
+ Value :: term(),
+ Map2 :: map().
+
+take(_,_) -> erlang:nif_error(undef).
-spec to_list(Map) -> [{Key,Value}] when
Map :: map(),
@@ -127,8 +134,40 @@ update(_,_,_) -> erlang:nif_error(undef).
values(_) -> erlang:nif_error(undef).
+%% End of BIFs
+
+-spec update_with(Key,Fun,Map1) -> Map2 when
+ Key :: term(),
+ Map1 :: map(),
+ Map2 :: map(),
+ Fun :: fun((Value1 :: term()) -> Value2 :: term()).
+
+update_with(Key,Fun,Map) when is_function(Fun,1), is_map(Map) ->
+ try maps:get(Key,Map) of
+ Val -> maps:update(Key,Fun(Val),Map)
+ catch
+ error:{badkey,_} ->
+ erlang:error({badkey,Key},[Key,Fun,Map])
+ end;
+update_with(Key,Fun,Map) ->
+ erlang:error(error_type(Map),[Key,Fun,Map]).
+
+
+-spec update_with(Key,Fun,Init,Map1) -> Map2 when
+ Key :: term(),
+ Map1 :: Map1,
+ Map2 :: Map2,
+ Fun :: fun((Value1 :: term()) -> Value2 :: term()),
+ Init :: term().
+
+update_with(Key,Fun,Init,Map) when is_function(Fun,1), is_map(Map) ->
+ case maps:find(Key,Map) of
+ {ok,Val} -> maps:update(Key,Fun(Val),Map);
+ error -> maps:put(Key,Init,Map)
+ end;
+update_with(Key,Fun,Init,Map) ->
+ erlang:error(error_type(Map),[Key,Fun,Init,Map]).
-%%% End of BIFs
-spec get(Key, Map, Default) -> Value | Default when
Key :: term(),
diff --git a/lib/stdlib/test/maps_SUITE.erl b/lib/stdlib/test/maps_SUITE.erl
index 8b3a8d7ae2..42e669a799 100644
--- a/lib/stdlib/test/maps_SUITE.erl
+++ b/lib/stdlib/test/maps_SUITE.erl
@@ -25,15 +25,10 @@
-include_lib("common_test/include/ct.hrl").
-%% Test server specific exports
--export([all/0]).
--export([suite/0]).
--export([init_per_suite/1]).
--export([end_per_suite/1]).
--export([init_per_testcase/2]).
--export([end_per_testcase/2]).
-
--export([t_get_3/1, t_filter_2/1,
+-export([all/0, suite/0]).
+
+-export([t_update_with_3/1, t_update_with_4/1,
+ t_get_3/1, t_filter_2/1,
t_fold_3/1,t_map_2/1,t_size_1/1,
t_with_2/1,t_without_2/1]).
@@ -41,29 +36,56 @@
%%-define(badarg(F,Args), {'EXIT', {badarg, [{maps,F,Args,_}|_]}}).
%% silly broken hipe
-define(badmap(V,F,_Args), {'EXIT', {{badmap,V}, [{maps,F,_,_}|_]}}).
+-define(badkey(K,F,_Args), {'EXIT', {{badkey,K}, [{maps,F,_,_}|_]}}).
-define(badarg(F,_Args), {'EXIT', {badarg, [{maps,F,_,_}|_]}}).
suite() ->
- [{ct_hooks, [ts_install_cth]},
+ [{ct_hooks,[ts_install_cth]},
{timetrap,{minutes,1}}].
all() ->
- [t_get_3,t_filter_2,
+ [t_update_with_3,t_update_with_4,
+ t_get_3,t_filter_2,
t_fold_3,t_map_2,t_size_1,
t_with_2,t_without_2].
-init_per_suite(Config) ->
- Config.
+t_update_with_3(Config) when is_list(Config) ->
+ V1 = value1,
+ V2 = <<"value2">>,
+ V3 = "value3",
+ Map = #{ key1 => V1, key2 => V2, "key3" => V3 },
+ Fun = fun(V) -> [V,V,{V,V}] end,
+
+ #{ key1 := [V1,V1,{V1,V1}] } = maps:update_with(key1,Fun,Map),
+ #{ key2 := [V2,V2,{V2,V2}] } = maps:update_with(key2,Fun,Map),
+ #{ "key3" := [V3,V3,{V3,V3}] } = maps:update_with("key3",Fun,Map),
-end_per_suite(_Config) ->
+ %% error case
+ ?badmap(b,update_with,[[a,b],a,b]) = (catch maps:update_with([a,b],id(a),b)),
+ ?badarg(update_with,[[a,b],a,#{}]) = (catch maps:update_with([a,b],id(a),#{})),
+ ?badkey([a,b],update_with,[[a,b],Fun,#{}]) = (catch maps:update_with([a,b],Fun,#{})),
ok.
-init_per_testcase(_Case, Config) ->
- Config.
+t_update_with_4(Config) when is_list(Config) ->
+ V1 = value1,
+ V2 = <<"value2">>,
+ V3 = "value3",
+ Map = #{ key1 => V1, key2 => V2, "key3" => V3 },
+ Fun = fun(V) -> [V,V,{V,V}] end,
+ Init = 3,
+
+ #{ key1 := [V1,V1,{V1,V1}] } = maps:update_with(key1,Fun,Init,Map),
+ #{ key2 := [V2,V2,{V2,V2}] } = maps:update_with(key2,Fun,Init,Map),
+ #{ "key3" := [V3,V3,{V3,V3}] } = maps:update_with("key3",Fun,Init,Map),
-end_per_testcase(_Case, _Config) ->
+ #{ key3 := Init } = maps:update_with(key3,Fun,Init,Map),
+
+ %% error case
+ ?badmap(b,update_with,[[a,b],a,b]) = (catch maps:update_with([a,b],id(a),b)),
+ ?badarg(update_with,[[a,b],a,#{}]) = (catch maps:update_with([a,b],id(a),#{})),
ok.
+
t_get_3(Config) when is_list(Config) ->
Map = #{ key1 => value1, key2 => value2 },
DefaultValue = "Default value",
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-04 12:48:19 +0000