diff options
| -rw-r--r-- | lib/stdlib/doc/src/maps.xml | 20 | ||||
| -rw-r--r-- | lib/stdlib/src/maps.erl | 18 | ||||
| -rw-r--r-- | lib/stdlib/test/Makefile | 3 | ||||
| -rw-r--r-- | lib/stdlib/test/maps_SUITE.erl | 69 |
4 files changed, 108 insertions, 2 deletions
diff --git a/lib/stdlib/doc/src/maps.xml b/lib/stdlib/doc/src/maps.xml index 76137e3dee..b37f7fd7fd 100644 --- a/lib/stdlib/doc/src/maps.xml +++ b/lib/stdlib/doc/src/maps.xml @@ -108,6 +108,26 @@ </func> <func> + <name name="get" arity="3"/> + <fsummary></fsummary> + <desc> + <p> + Returns the value <c><anno>Value</anno></c> associated with <c><anno>Key</anno></c> if + <c><anno>Map</anno></c> contains <c><anno>Key</anno></c>. + If no value is associated with <c><anno>Key</anno></c> then returns <c><anno>Default</anno></c>. + </p> + <p>Example:</p> + <code type="none"> +> Map = #{ key1 => val1, key2 => val2 }. +#{key1 => val1,key2 => val2} +> maps:get(key1, Map, "Default value"). +val1 +> maps:get(key3, Map, "Default value"). +"Default value"</code> + </desc> + </func> + + <func> <name name="is_key" arity="2"/> <fsummary></fsummary> <desc> diff --git a/lib/stdlib/src/maps.erl b/lib/stdlib/src/maps.erl index fd6d56fa47..4ef1638e6d 100644 --- a/lib/stdlib/src/maps.erl +++ b/lib/stdlib/src/maps.erl @@ -23,7 +23,8 @@ fold/3, map/2, size/1, - without/2 + without/2, + get/3 ]). @@ -142,6 +143,21 @@ 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(), diff --git a/lib/stdlib/test/Makefile b/lib/stdlib/test/Makefile index 39f6ce423a..a271229c59 100644 --- a/lib/stdlib/test/Makefile +++ b/lib/stdlib/test/Makefile @@ -85,7 +85,8 @@ MODULES= \ zip_SUITE \ random_unicode_list \ random_iolist \ - error_logger_forwarder + error_logger_forwarder \ + maps_SUITE ERL_FILES= $(MODULES:%=%.erl) diff --git a/lib/stdlib/test/maps_SUITE.erl b/lib/stdlib/test/maps_SUITE.erl new file mode 100644 index 0000000000..c826ee731a --- /dev/null +++ b/lib/stdlib/test/maps_SUITE.erl @@ -0,0 +1,69 @@ +%% +%% %CopyrightBegin% +%% +%% Copyright Ericsson AB 1997-2014. 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% +%% +%%%---------------------------------------------------------------- +%%% Purpose: Test suite for the 'maps' module. +%%%----------------------------------------------------------------- + +-module(maps_SUITE). + +-include_lib("test_server/include/test_server.hrl"). + +% Default timetrap timeout (set in init_per_testcase). +% This should be set relatively high (10-15 times the expected +% max testcasetime). +-define(default_timeout, ?t:minutes(4)). + +% 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([get3/1]). + +suite() -> + [{ct_hooks, [ts_install_cth]}]. + +all() -> + [get3]. + +init_per_suite(Config) -> + Config. + +end_per_suite(_Config) -> + ok. + +init_per_testcase(_Case, Config) -> + ?line Dog=test_server:timetrap(?default_timeout), + [{watchdog, Dog}|Config]. + +end_per_testcase(_Case, Config) -> + Dog=?config(watchdog, Config), + test_server:timetrap_cancel(Dog), + ok. + +get3(Config) when is_list(Config) -> + Map = #{ key1 => value1, key2 => value2 }, + DefaultValue = "Default value", + ?line value1 = maps:get(key1, Map, DefaultValue), + ?line value2 = maps:get(key2, Map, DefaultValue), + ?line DefaultValue = maps:get(key3, Map, DefaultValue), + ok. |