aboutsummaryrefslogtreecommitdiffstats
path: root/lib/stdlib/doc/src/maps.xml
diff options
context:
space:
mode:
Diffstat (limited to 'lib/stdlib/doc/src/maps.xml')
-rw-r--r--lib/stdlib/doc/src/maps.xml639
1 files changed, 336 insertions, 303 deletions
diff --git a/lib/stdlib/doc/src/maps.xml b/lib/stdlib/doc/src/maps.xml
index 48c1abc2f8..8c7270816b 100644
--- a/lib/stdlib/doc/src/maps.xml
+++ b/lib/stdlib/doc/src/maps.xml
@@ -2,12 +2,12 @@
<!DOCTYPE erlref SYSTEM "erlref.dtd">
<erlref>
- <header>
- <copyright>
- <year>2013</year><year>2014</year>
- <holder>Ericsson AB. All Rights Reserved.</holder>
- </copyright>
- <legalnotice>
+ <header>
+ <copyright>
+ <year>2013</year><year>2016</year>
+ <holder>Ericsson AB. All Rights Reserved.</holder>
+ </copyright>
+ <legalnotice>
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
@@ -19,394 +19,427 @@
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
- </legalnotice>
- <title>maps</title>
- <prepared>Björn-Egil Dahlberg</prepared>
- <docno>1</docno>
- <date>2014-02-28</date>
- <rev>A</rev>
- </header>
- <module>maps</module>
- <modulesummary>Maps Processing Functions</modulesummary>
- <description>
- <p>This module contains functions for maps processing.</p>
- </description>
- <funcs>
+ </legalnotice>
- <func>
- <name name="filter" arity="2"/>
- <fsummary>Choose pairs which satisfy a predicate</fsummary>
- <desc>
- <p>
- Returns a map <c><anno>Map2</anno></c> for which predicate
- <c><anno>Pred</anno></c> holds true in <c><anno>Map1</anno></c>.
- </p>
- <p>
- The call will fail with a <c>{badmap,Map}</c> exception if
- <c><anno>Map1</anno></c> is not a map or with <c>badarg</c> if
- <c><anno>Pred</anno></c> is not a function of arity 2.
- </p>
- <p>Example:</p>
- <code type="none">
+ <title>maps</title>
+ <prepared>Björn-Egil Dahlberg</prepared>
+ <docno>1</docno>
+ <date>2014-02-28</date>
+ <rev>A</rev>
+ </header>
+ <module>maps</module>
+ <modulesummary>Maps processing functions.</modulesummary>
+ <description>
+ <p>This module contains functions for maps processing.</p>
+ </description>
+
+ <funcs>
+ <func>
+ <name name="filter" arity="2"/>
+ <fsummary>Select pairs that satisfy a predicate.</fsummary>
+ <desc>
+ <p>Returns a map <c><anno>Map2</anno></c> for which predicate
+ <c><anno>Pred</anno></c> holds true in <c><anno>Map1</anno></c>.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map1</anno></c> is not a map, or with <c>badarg</c> if
+ <c><anno>Pred</anno></c> is not a function of arity 2.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> M = #{a => 2, b => 3, c=> 4, "a" => 1, "b" => 2, "c" => 4},
Pred = fun(K,V) -> is_atom(K) andalso (V rem 2) =:= 0 end,
maps:filter(Pred,M).
-#{a => 2,c => 4} </code>
- </desc>
- </func>
+#{a => 2,c => 4}</code>
+ </desc>
+ </func>
- <func>
- <name name="find" arity="2"/>
- <fsummary></fsummary>
- <desc>
- <p>
- Returns a tuple <c>{ok, Value}</c> where <c><anno>Value</anno></c> is the value associated with <c><anno>Key</anno></c>,
- or <c>error</c> if no value is associated with <c><anno>Key</anno></c> in <c><anno>Map</anno></c>.
- </p>
- <p>
- The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map</anno></c> is not a map.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="find" arity="2"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns a tuple <c>{ok, Value}</c>, where <c><anno>Value</anno></c>
+ is the value associated with <c><anno>Key</anno></c>, or <c>error</c>
+ if no value is associated with <c><anno>Key</anno></c> in
+ <c><anno>Map</anno></c>.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map</anno></c> is not a map.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{"hi" => 42},
Key = "hi",
maps:find(Key,Map).
-{ok,42} </code>
- </desc>
- </func>
+{ok,42}</code>
+ </desc>
+ </func>
- <func>
- <name name="fold" arity="3"/>
- <fsummary></fsummary>
- <desc>
- <p>
- Calls <c>F(K, V, AccIn)</c> for every <c><anno>K</anno></c> to value <c><anno>V</anno></c>
- association in <c><anno>Map</anno></c> in
- arbitrary order. The function <c>fun F/3</c> must return a new accumulator
- which is passed to the next successive call. <c>maps:fold/3</c> returns the final
- value of the accumulator. The initial accumulator value <c><anno>Init</anno></c> is returned if
- the map is empty.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="fold" arity="3"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Calls <c>F(K, V, AccIn)</c> for every <c><anno>K</anno></c> to value
+ <c><anno>V</anno></c> association in <c><anno>Map</anno></c> in
+ any order. Function <c>fun F/3</c> must return a new
+ accumulator, which is passed to the next successive call.
+ This function returns the final value of the accumulator. The initial
+ accumulator value <c><anno>Init</anno></c> is returned if the map is
+ empty.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Fun = fun(K,V,AccIn) when is_list(K) -> AccIn + V end,
Map = #{"k1" => 1, "k2" => 2, "k3" => 3},
maps:fold(Fun,0,Map).
6</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="from_list" arity="1"/>
- <fsummary></fsummary>
- <desc>
- <p>
- The function takes a list of key-value tuples elements and builds a
- map. The associations may be in any order and both keys and values in the
- association may be of any term. If the same key appears more than once,
- the latter (rightmost) value is used and the previous values are ignored.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="from_list" arity="1"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Takes a list of key-value tuples elements and builds a map. The
+ associations can be in any order, and both keys and values in the
+ association can be of any term. If the same key appears more than
+ once, the latter (right-most) value is used and the previous values
+ are ignored.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> List = [{"a",ignored},{1337,"value two"},{42,value_three},{"a",1}],
maps:from_list(List).
#{42 => value_three,1337 => "value two","a" => 1}</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="get" arity="2"/>
- <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>.
- </p>
- <p>
- The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map</anno></c> is not a map,
- or with a <c>{badkey,Key}</c> exception if no value is associated with <c><anno>Key</anno></c>.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="get" arity="2"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns 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>.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map</anno></c> is not a map, or with a <c>{badkey,Key}</c>
+ exception if no value is associated with <c><anno>Key</anno></c>.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Key = 1337,
Map = #{42 => value_two,1337 => "value one","a" => 1},
maps:get(Key,Map).
"value one"</code>
- </desc>
- </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>
- The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map</anno></c> is not a map.
+ </desc>
+ </func>
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="get" arity="3"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns 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>, <c><anno>Default</anno></c> is returned.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map</anno></c> is not a map.</p>
+ <p><em>Example:</em></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>
+ </desc>
+ </func>
- <func>
- <name name="is_key" arity="2"/>
- <fsummary></fsummary>
- <desc>
- <p>
- Returns <c>true</c> if map <c><anno>Map</anno></c> contains <c><anno>Key</anno></c> and returns
- <c>false</c> if it does not contain the <c><anno>Key</anno></c>.
- </p>
- <p>
- The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map</anno></c> is not a map.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="is_key" arity="2"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns <c>true</c> if map <c><anno>Map</anno></c> contains
+ <c><anno>Key</anno></c> and returns <c>false</c> if it does not
+ contain the <c><anno>Key</anno></c>.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map</anno></c> is not a map.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{"42" => value}.
-#{"42"> => value}
+#{"42" => value}
> maps:is_key("42",Map).
true
> maps:is_key(value,Map).
false</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="keys" arity="1"/>
- <fsummary></fsummary>
- <desc>
- <p>
- Returns a complete list of keys, in arbitrary order, which resides within <c><anno>Map</anno></c>.
- </p>
- <p>
- The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map</anno></c> is not a map.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="keys" arity="1"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns a complete list of keys, in any order, which resides
+ within <c><anno>Map</anno></c>.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map</anno></c> is not a map.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{42 => value_three,1337 => "value two","a" => 1},
maps:keys(Map).
[42,1337,"a"]</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="map" arity="2"/>
- <fsummary></fsummary>
- <desc>
- <p>
- The function produces a new map <c><anno>Map2</anno></c> by calling the function <c>fun F(K, V1)</c> for
- every <c><anno>K</anno></c> to value <c><anno>V1</anno></c> association in <c><anno>Map1</anno></c> in arbitrary order.
- The function <c>fun F/2</c> must return the value <c><anno>V2</anno></c> to be associated with key <c><anno>K</anno></c> for
- the new map <c><anno>Map2</anno></c>.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="map" arity="2"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Produces a new map <c><anno>Map2</anno></c> by calling function
+ <c>fun F(K, V1)</c> for every <c><anno>K</anno></c> to value
+ <c><anno>V1</anno></c> association in <c><anno>Map1</anno></c> in
+ any order. Function <c>fun F/2</c> must return value
+ <c><anno>V2</anno></c> to be associated with key <c><anno>K</anno></c>
+ for the new map <c><anno>Map2</anno></c>.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Fun = fun(K,V1) when is_list(K) -> V1*2 end,
Map = #{"k1" => 1, "k2" => 2, "k3" => 3},
maps:map(Fun,Map).
#{"k1" => 2,"k2" => 4,"k3" => 6}</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="merge" arity="2"/>
- <fsummary></fsummary>
- <desc>
- <p>
- Merges two maps into a single map <c><anno>Map3</anno></c>. If two keys exists in both maps the
- value in <c><anno>Map1</anno></c> will be superseded by the value in <c><anno>Map2</anno></c>.
- </p>
- <p>
- The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map1</anno></c> or
- <c><anno>Map2</anno></c> is not a map.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="merge" arity="2"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Merges two maps into a single map <c><anno>Map3</anno></c>. If two
+ keys exist in both maps, the value in <c><anno>Map1</anno></c> is
+ superseded by the value in <c><anno>Map2</anno></c>.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map1</anno></c> or <c><anno>Map2</anno></c> is not a map.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map1 = #{a => "value_one", b => "value_two"},
Map2 = #{a => 1, c => 2},
maps:merge(Map1,Map2).
#{a => 1,b => "value_two",c => 2}</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="new" arity="0"/>
- <fsummary></fsummary>
- <desc>
- <p>
- Returns a new empty map.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="new" arity="0"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns a new empty map.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> maps:new().
#{}</code>
- </desc>
- </func>
-
- <func>
- <name name="put" arity="3"/>
- <fsummary></fsummary>
- <desc>
- <p>
- Associates <c><anno>Key</anno></c> with value <c><anno>Value</anno></c> and inserts the association into map <c>Map2</c>.
- If key <c><anno>Key</anno></c> already exists in map <c><anno>Map1</anno></c>, the old associated value is
- replaced by value <c><anno>Value</anno></c>. The function returns a new map <c><anno>Map2</anno></c> containing the new association and
- the old associations in <c><anno>Map1</anno></c>.
- </p>
- <p>
- The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map1</anno></c> is not a map.
- </p>
+ </desc>
+ </func>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="put" arity="3"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Associates <c><anno>Key</anno></c> with value
+ <c><anno>Value</anno></c> and inserts the association into map
+ <c>Map2</c>. If key <c><anno>Key</anno></c> already exists in map
+ <c><anno>Map1</anno></c>, the old associated value is replaced by
+ value <c><anno>Value</anno></c>. The function returns a new map
+ <c><anno>Map2</anno></c> containing the new association and the old
+ associations in <c><anno>Map1</anno></c>.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map1</anno></c> is not a map.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{"a" => 1}.
#{"a" => 1}
> maps:put("a", 42, Map).
#{"a" => 42}
> maps:put("b", 1337, Map).
#{"a" => 1,"b" => 1337}</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="remove" 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 new map <c><anno>Map2</anno></c> without key <c><anno>Key</anno></c>.
- </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">
+ <func>
+ <name name="remove" arity="2"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Removes the <c><anno>Key</anno></c>, if it exists, and its
+ associated value from <c><anno>Map1</anno></c> and returns a new map
+ <c><anno>Map2</anno></c> without key <c><anno>Key</anno></c>.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map1</anno></c> is not a map.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{"a" => 1}.
#{"a" => 1}
> maps:remove("a",Map).
#{}
> maps:remove("b",Map).
#{"a" => 1}</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="size" arity="1"/>
- <fsummary></fsummary>
- <desc>
- <p>
- The function returns the number of key-value associations in the <c><anno>Map</anno></c>.
- This operation happens in constant time.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="size" arity="1"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns the number of key-value associations in
+ <c><anno>Map</anno></c>. This operation occurs in constant time.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{42 => value_two,1337 => "value one","a" => 1},
maps:size(Map).
3</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="to_list" arity="1"/>
- <fsummary></fsummary>
- <desc>
- <p>
- The fuction returns a list of pairs representing the key-value associations of <c><anno>Map</anno></c>,
- where the pairs, <c>[{K1,V1}, ..., {Kn,Vn}]</c>, are returned in arbitrary order.
- </p>
- <p>
- The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map</anno></c> is not a map.
- </p>
- <p>Example:</p>
- <code type="none">
+ <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="to_list" arity="1"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns a list of pairs representing the key-value associations of
+ <c><anno>Map</anno></c>, where the pairs
+ <c>[{K1,V1}, ..., {Kn,Vn}]</c> are returned in arbitrary order.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map</anno></c> is not a map.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{42 => value_three,1337 => "value two","a" => 1},
maps:to_list(Map).
[{42,value_three},{1337,"value two"},{"a",1}]</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="update" arity="3"/>
- <fsummary></fsummary>
- <desc>
- <p>
- If <c><anno>Key</anno></c> exists in <c><anno>Map1</anno></c> the old associated value is
- replaced by value <c><anno>Value</anno></c>. The function returns a new map <c><anno>Map2</anno></c> containing
- the new associated value.
- </p>
- <p>
- The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map1</anno></c> is not a map,
- or with a <c>{badkey,Key}</c> exception if no value is associated with <c><anno>Key</anno></c>.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="update" arity="3"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>If <c><anno>Key</anno></c> exists in <c><anno>Map1</anno></c>, the
+ old associated value is replaced by value <c><anno>Value</anno></c>.
+ The function returns a new map <c><anno>Map2</anno></c> containing
+ the new associated value.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map1</anno></c> is not a map, or with a <c>{badkey,Key}</c>
+ exception if no value is associated with <c><anno>Key</anno></c>.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{"a" => 1}.
#{"a" => 1}
> maps:update("a", 42, Map).
#{"a" => 42}</code>
- </desc>
- </func>
+ </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>
- <desc>
- <p>
- Returns a complete list of values, in arbitrary order, contained in map <c>Map</c>.
- </p>
- <p>
- The call will fail with a <c>{badmap,Map}</c> exception if <c><anno>Map</anno></c> is not a map.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="values" arity="1"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns a complete list of values, in arbitrary order, contained in
+ map <c>Map</c>.</p>
+ <p>The call fails with a <c>{badmap,Map}</c> exception if
+ <c><anno>Map</anno></c> is not a map.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{42 => value_three,1337 => "value two","a" => 1},
maps:values(Map).
[value_three,"value two",1]</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="with" arity="2"/>
- <fsummary></fsummary>
- <desc>
- <p>
- Returns a new map <c><anno>Map2</anno></c> with the keys <c>K1</c> through <c>Kn</c> and their associated values from map <c><anno>Map1</anno></c>.
- Any key in <c><anno>Ks</anno></c> that does not exist in <c><anno>Map1</anno></c> are ignored.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="with" arity="2"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns a new map <c><anno>Map2</anno></c> with the keys <c>K1</c>
+ through <c>Kn</c> and their associated values from map
+ <c><anno>Map1</anno></c>. Any key in <c><anno>Ks</anno></c> that does
+ not exist in <c><anno>Map1</anno></c> is ignored.</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{42 => value_three,1337 => "value two","a" => 1},
Ks = ["a",42,"other key"],
maps:with(Ks,Map).
#{42 => value_three,"a" => 1}</code>
- </desc>
- </func>
+ </desc>
+ </func>
- <func>
- <name name="without" arity="2"/>
- <fsummary></fsummary>
- <desc>
- <p>
- Returns a new map <c><anno>Map2</anno></c> without the keys <c>K1</c> through <c>Kn</c> and their associated values from map <c><anno>Map1</anno></c>.
- Any key in <c><anno>Ks</anno></c> that does not exist in <c><anno>Map1</anno></c> are ignored.
- </p>
- <p>Example:</p>
- <code type="none">
+ <func>
+ <name name="without" arity="2"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>Returns a new map <c><anno>Map2</anno></c> without keys <c>K1</c>
+ through <c>Kn</c> and their associated values from map
+ <c><anno>Map1</anno></c>. Any key in <c><anno>Ks</anno></c> that does
+ not exist in <c><anno>Map1</anno></c> is ignored</p>
+ <p><em>Example:</em></p>
+ <code type="none">
> Map = #{42 => value_three,1337 => "value two","a" => 1},
Ks = ["a",42,"other key"],
maps:without(Ks,Map).
#{1337 => "value two"}</code>
- </desc>
- </func>
- </funcs>
+ </desc>
+ </func>
+ </funcs>
</erlref>