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-rw-r--r--lib/stdlib/doc/src/Makefile1
-rw-r--r--lib/stdlib/doc/src/epp.xml64
-rw-r--r--lib/stdlib/doc/src/erl_parse.xml10
-rw-r--r--lib/stdlib/doc/src/maps.xml318
-rw-r--r--lib/stdlib/doc/src/ref_man.xml1
-rw-r--r--lib/stdlib/doc/src/specs.xml1
-rw-r--r--lib/stdlib/doc/src/supervisor.xml6
-rw-r--r--lib/stdlib/doc/src/sys.xml73
-rw-r--r--lib/stdlib/doc/src/unicode_usage.xml4
9 files changed, 461 insertions, 17 deletions
diff --git a/lib/stdlib/doc/src/Makefile b/lib/stdlib/doc/src/Makefile
index 6f1e61e70c..ff77c3eea0 100644
--- a/lib/stdlib/doc/src/Makefile
+++ b/lib/stdlib/doc/src/Makefile
@@ -71,6 +71,7 @@ XML_REF3_FILES = \
lib.xml \
lists.xml \
log_mf_h.xml \
+ maps.xml \
math.xml \
ms_transform.xml \
orddict.xml \
diff --git a/lib/stdlib/doc/src/epp.xml b/lib/stdlib/doc/src/epp.xml
index cf33530395..452341f7d2 100644
--- a/lib/stdlib/doc/src/epp.xml
+++ b/lib/stdlib/doc/src/epp.xml
@@ -4,7 +4,7 @@
<erlref>
<header>
<copyright>
- <year>1996</year><year>2013</year>
+ <year>1996</year><year>2014</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -46,8 +46,10 @@
valid encodings are <c>Latin-1</c> and <c>UTF-8</c> where the
case of the characters can be chosen freely. Examples:</p>
<pre>
-%% coding: utf-8
-%% For this file we have chosen encoding = Latin-1
+%% coding: utf-8</pre>
+ <pre>
+%% For this file we have chosen encoding = Latin-1</pre>
+ <pre>
%% -*- coding: latin-1 -*-</pre>
</description>
<datatypes>
@@ -64,11 +66,29 @@
</datatypes>
<funcs>
<func>
+ <name name="open" arity="1"/>
+ <fsummary>Open a file for preprocessing</fsummary>
+ <desc>
+ <p>Opens a file for preprocessing.</p>
+ <p>If <c>extra</c> is given in
+ <c><anno>Options</anno></c>, the return value will be
+ <c>{ok, <anno>Epp</anno>, <anno>Extra</anno>}</c> instead
+ of <c>{ok, <anno>Epp</anno>}</c>.</p>
+ </desc>
+ </func>
+ <func>
<name name="open" arity="2"/>
+ <fsummary>Open a file for preprocessing</fsummary>
+ <desc>
+ <p>Equivalent to <c>epp:open([{name, FileName}, {includes, IncludePath}])</c>.</p>
+ </desc>
+ </func>
+ <func>
<name name="open" arity="3"/>
<fsummary>Open a file for preprocessing</fsummary>
<desc>
- <p>Opens a file for preprocessing.</p>
+ <p>Equivalent to <c>epp:open([{name, FileName}, {includes, IncludePath},
+ {macros, PredefMacros}])</c>.</p>
</desc>
</func>
<func>
@@ -89,12 +109,24 @@
</desc>
</func>
<func>
- <name name="parse_file" arity="3"/>
+ <name name="parse_file" arity="2"/>
<fsummary>Preprocess and parse an Erlang source file</fsummary>
<desc>
<p>Preprocesses and parses an Erlang source file.
- Note that the tuple <c>{eof, <anno>Line</anno>}</c> returned at end-of-file is
- included as a "form".</p>
+ Note that the tuple <c>{eof, <anno>Line</anno>}</c> returned
+ at end-of-file is included as a "form".</p>
+ <p>If <c>extra</c> is given in
+ <c><anno>Options</anno></c>, the return value will be
+ <c>{ok, [<anno>Form</anno>], <anno>Extra</anno>}</c> instead
+ of <c>{ok, [<anno>Form</anno>]}</c>.</p>
+ </desc>
+ </func>
+ <func>
+ <name name="parse_file" arity="3"/>
+ <fsummary>Preprocess and parse an Erlang source file</fsummary>
+ <desc>
+ <p>Equivalent to <c>epp:parse_file(FileName, [{includes, IncludePath},
+ {macros, PredefMacros}])</c>.</p>
</desc>
</func>
<func>
@@ -111,7 +143,7 @@
<p>Returns a string representation of an encoding. The string
is recognized by <c>read_encoding/1,2</c>,
<c>read_encoding_from_binary/1,2</c>, and
- <c>set_encoding/1</c> as a valid encoding.</p>
+ <c>set_encoding/1,2</c> as a valid encoding.</p>
</desc>
</func>
<func>
@@ -157,6 +189,22 @@
</desc>
</func>
<func>
+ <name name="set_encoding" arity="2"/>
+ <fsummary>Read and set the encoding of an IO device</fsummary>
+ <desc>
+ <p>Reads the <seealso marker="#encoding">encoding</seealso> from
+ an IO device and sets the encoding of the device
+ accordingly. The position of the IO device referenced by
+ <c><anno>File</anno></c> is not affected. If no valid
+ encoding can be read from the IO device the encoding of the
+ IO device is set to the
+ <seealso marker="#encoding">encoding</seealso> given by
+ <c><anno>Default</anno></c>.</p>
+ <p>Returns the read encoding, or <c>none</c> if no valid
+ encoding was found.</p>
+ </desc>
+ </func>
+ <func>
<name name="format_error" arity="1"/>
<fsummary>Format an error descriptor</fsummary>
<desc>
diff --git a/lib/stdlib/doc/src/erl_parse.xml b/lib/stdlib/doc/src/erl_parse.xml
index 2d5aff3c6c..cf0bff48cd 100644
--- a/lib/stdlib/doc/src/erl_parse.xml
+++ b/lib/stdlib/doc/src/erl_parse.xml
@@ -4,7 +4,7 @@
<erlref>
<header>
<copyright>
- <year>1996</year><year>2013</year>
+ <year>1996</year><year>2014</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -173,6 +173,7 @@
</func>
<func>
<name name="abstract" arity="2"/>
+ <type name="encoding_func"/>
<fsummary>Convert an Erlang term into an abstract form</fsummary>
<desc>
<p>Converts the Erlang data structure <c><anno>Data</anno></c> into an
@@ -183,7 +184,12 @@
selecting which integer lists will be considered
as strings. The default is to use the encoding returned by
<seealso marker="epp#default_encoding/0">
- <c>epp:default_encoding/0</c></seealso></p>
+ <c>epp:default_encoding/0</c></seealso>.
+ The value <c>none</c> means that no integer lists will be
+ considered as strings. The <c>encoding_func()</c> will be
+ called with one integer of a list at a time, and if it
+ returns <c>true</c> for every integer the list will be
+ considered a string.</p>
</desc>
</func>
</funcs>
diff --git a/lib/stdlib/doc/src/maps.xml b/lib/stdlib/doc/src/maps.xml
new file mode 100644
index 0000000000..76137e3dee
--- /dev/null
+++ b/lib/stdlib/doc/src/maps.xml
@@ -0,0 +1,318 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!DOCTYPE erlref SYSTEM "erlref.dtd">
+
+<erlref>
+ <header>
+ <copyright>
+ <year>2013</year><year>2014</year>
+ <holder>Ericsson AB. All Rights Reserved.</holder>
+ </copyright>
+ <legalnotice>
+ 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.
+ </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>
+
+ <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>Example:</p>
+ <code type="none">
+> Map = #{"hi" => 42},
+ Key = "hi",
+ maps:find(Key,Map).
+{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">
+> 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>
+
+ <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">
+> 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>
+
+ <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>.
+ If no value is associated with <c><anno>Key</anno></c> then the call will
+ fail with an exception.
+ </p>
+ <p>Example:</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="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>.
+ The function will fail with an exception if <c><anno>Map</anno></c> is not a Map.
+ </p>
+ <p>Example:</p>
+ <code type="none">
+> Map = #{"42" => value}.
+#{"42"> => value}
+> maps:is_key("42",Map).
+true
+> maps:is_key(value,Map).
+false</code>
+ </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>Example:</p>
+ <code type="none">
+> Map = #{42 => value_three,1337 => "value two","a" => 1},
+ maps:keys(Map).
+[42,1337,"a"]</code>
+ </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">
+> 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>
+
+ <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>Example:</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>
+
+ <func>
+ <name name="new" arity="0"/>
+ <fsummary></fsummary>
+ <desc>
+ <p>
+ Returns a new empty map.
+ </p>
+ <p>Example:</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>Example:</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>
+
+ <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>Example:</p>
+ <code type="none">
+> Map = #{"a" => 1}.
+#{"a" => 1}
+> maps:remove("a",Map).
+#{}
+> maps:remove("b",Map).
+#{"a" => 1}</code>
+ </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">
+> Map = #{42 => value_two,1337 => "value one","a" => 1},
+ maps:size(Map).
+3</code>
+ </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>Example:</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>
+
+ <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. If <c><anno>Key</anno></c> does not exist in <c><anno>Map1</anno></c> an exception is
+ generated.
+ </p>
+ <p>Example:</p>
+ <code type="none">
+> Map = #{"a" => 1}.
+#{"a" => 1}
+> maps:update("a", 42, Map).
+#{"a" => 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>M</c>.
+ </p>
+ <p>Example:</p>
+ <code type="none">
+> Map = #{42 => value_three,1337 => "value two","a" => 1},
+ maps:values(Map).
+[value_three,"value two",1]</code>
+ </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">
+> 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>
+</erlref>
diff --git a/lib/stdlib/doc/src/ref_man.xml b/lib/stdlib/doc/src/ref_man.xml
index 4ecd02a4bf..6c35578bdf 100644
--- a/lib/stdlib/doc/src/ref_man.xml
+++ b/lib/stdlib/doc/src/ref_man.xml
@@ -68,6 +68,7 @@
<xi:include href="lib.xml"/>
<xi:include href="lists.xml"/>
<xi:include href="log_mf_h.xml"/>
+ <xi:include href="maps.xml"/>
<xi:include href="math.xml"/>
<xi:include href="ms_transform.xml"/>
<xi:include href="orddict.xml"/>
diff --git a/lib/stdlib/doc/src/specs.xml b/lib/stdlib/doc/src/specs.xml
index 213ce7563f..60a04ed5e7 100644
--- a/lib/stdlib/doc/src/specs.xml
+++ b/lib/stdlib/doc/src/specs.xml
@@ -34,6 +34,7 @@
<xi:include href="../specs/specs_lib.xml"/>
<xi:include href="../specs/specs_lists.xml"/>
<xi:include href="../specs/specs_log_mf_h.xml"/>
+ <xi:include href="../specs/specs_maps.xml"/>
<xi:include href="../specs/specs_math.xml"/>
<xi:include href="../specs/specs_ms_transform.xml"/>
<xi:include href="../specs/specs_orddict.xml"/>
diff --git a/lib/stdlib/doc/src/supervisor.xml b/lib/stdlib/doc/src/supervisor.xml
index 8197684d2d..3a5027d595 100644
--- a/lib/stdlib/doc/src/supervisor.xml
+++ b/lib/stdlib/doc/src/supervisor.xml
@@ -4,7 +4,7 @@
<erlref>
<header>
<copyright>
- <year>1996</year><year>2013</year>
+ <year>1996</year><year>2014</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -262,12 +262,12 @@ child_spec() = {Id,StartFunc,Restart,Shutdown,Type,Modules}
locally as <c>Name</c> using <c>register/2</c>. If
<c><anno>SupName</anno>={global,Name}</c> the supervisor is registered
globally as <c>Name</c> using <c>global:register_name/2</c>. If
- <c><anno>SupName</anno>={via,Module,Name}</c> the supervisor
+ <c><anno>SupName</anno>={via,<anno>Module</anno>,<anno>Name</anno>}</c> the supervisor
is registered as <c>Name</c> using the registry represented by
<c>Module</c>. The <c>Module</c> callback should export the functions
<c>register_name/2</c>, <c>unregister_name/1</c> and <c>send/2</c>,
which should behave like the corresponding functions in <c>global</c>.
- Thus, <c>{via,global,Name}</c> is a valid reference.</p>
+ Thus, <c>{via,global,<anno>Name</anno>}</c> is a valid reference.</p>
<p>If no name is provided, the supervisor is not registered.</p>
<p><c><anno>Module</anno></c> is the name of the callback module.</p>
<p><c><anno>Args</anno></c> is an arbitrary term which is passed as
diff --git a/lib/stdlib/doc/src/sys.xml b/lib/stdlib/doc/src/sys.xml
index ab8b380f49..a46fa1289f 100644
--- a/lib/stdlib/doc/src/sys.xml
+++ b/lib/stdlib/doc/src/sys.xml
@@ -246,6 +246,22 @@
<c>{Module, Id, HandlerState}</c>, where <c>Module</c> is the event handler's module name,
<c>Id</c> is the handler's ID (which is the value <c>false</c> if it was registered without
an ID), and <c>HandlerState</c> is the handler's state.</p>
+ <p>If the callback module exports a <c>system_get_state/1</c> function, it will be called in the
+ target process to get its state. Its argument is the same as the <c>Misc</c> value returned by
+ <seealso marker="#get_status-1">get_status/1,2</seealso>, and the <c>system_get_state/1</c>
+ function is expected to extract the callback module's state from it. The <c>system_get_state/1</c>
+ function must return <c>{ok, State}</c> where <c>State</c> is the callback module's state.</p>
+ <p>If the callback module does not export a <c>system_get_state/1</c> function, <c>get_state/1,2</c>
+ assumes the <c>Misc</c> value is the callback module's state and returns it directly instead.</p>
+ <p>If the callback module's <c>system_get_state/1</c> function crashes or throws an exception, the
+ caller exits with error <c>{callback_failed, {Module, system_get_state}, {Class, Reason}}</c> where
+ <c>Module</c> is the name of the callback module and <c>Class</c> and <c>Reason</c> indicate
+ details of the exception.</p>
+ <p>The <c>system_get_state/1</c> function is primarily useful for user-defined
+ behaviours and modules that implement OTP <seealso marker="#special_process">special
+ processes</seealso>. The <c>gen_server</c>, <c>gen_fsm</c>, and <c>gen_event</c> OTP
+ behaviour modules export this function, and so callback modules for those behaviours
+ need not supply their own.</p>
<p>To obtain more information about a process, including its state, see
<seealso marker="#get_status-1">get_status/1</seealso> and
<seealso marker="#get_status-2">get_status/2</seealso>.</p>
@@ -289,6 +305,28 @@
function means that only the state of the particular event handler it was working on when it
failed or crashed is unchanged; it can still succeed in changing the states of other event
handlers registered in the same <c>gen_event</c> process.</p>
+ <p>If the callback module exports a <c>system_replace_state/2</c> function, it will be called in the
+ target process to replace its state using <c>StateFun</c>. Its two arguments are <c>StateFun</c>
+ and <c>Misc</c>, where <c>Misc</c> is the same as the <c>Misc</c> value returned by
+ <seealso marker="#get_status-1">get_status/1,2</seealso>. A <c>system_replace_state/2</c> function
+ is expected to return <c>{ok, NewState, NewMisc}</c> where <c>NewState</c> is the callback module's
+ new state obtained by calling <c>StateFun</c>, and <c>NewMisc</c> is a possibly new value used to
+ replace the original <c>Misc</c> (required since <c>Misc</c> often contains the callback
+ module's state within it).</p>
+ <p>If the callback module does not export a <c>system_replace_state/2</c> function,
+ <c>replace_state/2,3</c> assumes the <c>Misc</c> value is the callback module's state, passes it
+ to <c>StateFun</c> and uses the return value as both the new state and as the new value of
+ <c>Misc</c>.</p>
+ <p>If the callback module's <c>system_replace_state/2</c> function crashes or throws an exception,
+ the caller exits with error <c>{callback_failed, {Module, system_replace_state}, {Class, Reason}}</c>
+ where <c>Module</c> is the name of the callback module and <c>Class</c> and <c>Reason</c> indicate details
+ of the exception. If the callback module does not provide a <c>system_replace_state/2</c> function and
+ <c>StateFun</c> crashes or throws an exception, the caller exits with error
+ <c>{callback_failed, StateFun, {Class, Reason}}</c>.</p>
+ <p>The <c>system_replace_state/2</c> function is primarily useful for user-defined behaviours and
+ modules that implement OTP <seealso marker="#special_process">special processes</seealso>. The
+ <c>gen_server</c>, <c>gen_fsm</c>, and <c>gen_event</c> OTP behaviour modules export this function,
+ and so callback modules for those behaviours need not supply their own.</p>
</desc>
</func>
<func>
@@ -322,7 +360,7 @@
<section>
<title>Process Implementation Functions</title>
- <p>The following functions are used when implementing a
+ <p><marker id="special_process"/>The following functions are used when implementing a
special process. This is an ordinary process which does not use a
standard behaviour, but a process which understands the standard system messages.</p>
</section>
@@ -375,8 +413,9 @@
process continues the execution, or
<c><anno>Module</anno>:system_terminate(Reason, <anno>Parent</anno>, <anno>Debug</anno>, <anno>Misc</anno>)</c> if
the process should terminate. The <c><anno>Module</anno></c> must export
- <c>system_continue/3</c>, <c>system_terminate/4</c>, and
- <c>system_code_change/4</c> (see below).
+ <c>system_continue/3</c>, <c>system_terminate/4</c>,
+ <c>system_code_change/4</c>, <c>system_get_state/1</c> and
+ <c>system_replace_state/2</c> (see below).
</p>
<p>The <c><anno>Misc</anno></c> argument can be used to save internal data
in a process, for example its state. It is sent to
@@ -444,6 +483,34 @@
defined, the atom <c>undefined</c> is sent.</p>
</desc>
</func>
+ <func>
+ <name>Mod:system_get_state(Misc) -> {ok, State}</name>
+ <fsummary>Called when the process should return its current state</fsummary>
+ <type>
+ <v>Misc = term()</v>
+ <v>State = term()</v>
+ </type>
+ <desc>
+ <p>This function is called from <c>sys:handle_system_msg/6</c> when the process
+ should return a term that reflects its current state. <c>State</c> is the
+ value returned by <c>sys:get_state/2</c>.</p>
+ </desc>
+ </func>
+ <func>
+ <name>Mod:system_replace_state(StateFun, Misc) -> {ok, NState, NMisc}</name>
+ <fsummary>Called when the process should replace its current state</fsummary>
+ <type>
+ <v>StateFun = fun((State :: term()) -> NState)</v>
+ <v>Misc = term()</v>
+ <v>NState = term()</v>
+ <v>NMisc = term()</v>
+ </type>
+ <desc>
+ <p>This function is called from <c>sys:handle_system_msg/6</c> when the process
+ should replace its current state. <c>NState</c> is the value returned by
+ <c>sys:replace_state/3</c>.</p>
+ </desc>
+ </func>
</funcs>
</erlref>
diff --git a/lib/stdlib/doc/src/unicode_usage.xml b/lib/stdlib/doc/src/unicode_usage.xml
index 75505d7d84..bebfbd4514 100644
--- a/lib/stdlib/doc/src/unicode_usage.xml
+++ b/lib/stdlib/doc/src/unicode_usage.xml
@@ -848,6 +848,7 @@ Eshell V5.10.1 (abort with ^G)
</section>
<section>
<title>Unicode in Environment and Parameters</title>
+ <marker id="unicode_in_environment_and_parameters"/>
<p>Environment variables and their interpretation is handled much in
the same way as file names. If Unicode file names are enabled,
environment variables as well as parameters to the Erlang VM are
@@ -996,7 +997,8 @@ ok
</pre>
</section>
<section>
- <title><marker id="unicode_options_summary"/>Summary of Options</title>
+ <title>Summary of Options</title>
+ <marker id="unicode_options_summary"/>
<p>The Unicode support is controlled by both command line switches,
some standard environment variables and the version of OTP you are
using. Most options affect mainly the way Unicode data is displayed,