diff options
Diffstat (limited to 'lib/stdlib/doc')
| -rw-r--r-- | lib/stdlib/doc/src/beam_lib.xml | 39 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/calendar.xml | 2 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/dets.xml | 4 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/digraph_utils.xml | 2 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/erl_pp.xml | 6 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/ets.xml | 62 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/filename.xml | 2 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/gen_statem.xml | 332 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/maps.xml | 34 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/notes.xml | 6 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/proc_lib.xml | 2 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/qlc.xml | 81 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/rand.xml | 110 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/slave.xml | 23 | ||||
| -rw-r--r-- | lib/stdlib/doc/src/sys.xml | 171 |
15 files changed, 632 insertions, 244 deletions
diff --git a/lib/stdlib/doc/src/beam_lib.xml b/lib/stdlib/doc/src/beam_lib.xml index 8bb4cf9101..bb44ca3201 100644 --- a/lib/stdlib/doc/src/beam_lib.xml +++ b/lib/stdlib/doc/src/beam_lib.xml @@ -470,6 +470,18 @@ CryptoKeyFun(clear) -> term()</code> </func> <func> + <name name="strip" arity="2" since=""/> + <fsummary>Remove chunks not needed by the loader from a BEAM file. + </fsummary> + <desc> + <p>Removes all chunks from a BEAM + file except those needed by the loader or passed in. In particular, + the debug information (chunk <c>debug_info</c> and <c>abstract_code</c>) + is removed.</p> + </desc> + </func> + + <func> <name name="strip_files" arity="1" since=""/> <fsummary>Removes chunks not needed by the loader from BEAM files. </fsummary> @@ -483,6 +495,19 @@ CryptoKeyFun(clear) -> term()</code> </func> <func> + <name name="strip_files" arity="2" since=""/> + <fsummary>Removes chunks not needed by the loader from BEAM files. + </fsummary> + <desc> + <p>Removes all chunks except + those needed by the loader or passed in from BEAM files. In particular, + the debug information (chunk <c>debug_info</c> and <c>abstract_code</c>) + is removed. The returned list contains one element for each + specified filename, in the same order as in <c>Files</c>.</p> + </desc> + </func> + + <func> <name name="strip_release" arity="1" since=""/> <fsummary>Remove chunks not needed by the loader from all BEAM files of a release.</fsummary> @@ -497,6 +522,20 @@ CryptoKeyFun(clear) -> term()</code> </func> <func> + <name name="strip_release" arity="2" since=""/> + <fsummary>Remove chunks not needed by the loader from all BEAM files of + a release.</fsummary> + <desc> + <p>Removes all chunks + except those needed by the loader or passed in from the BEAM files of a + release. <c><anno>Dir</anno></c> is to be the installation root + directory. For example, the current OTP release can be + stripped with the call + <c>beam_lib:strip_release(code:root_dir())</c>.</p> + </desc> + </func> + + <func> <name name="version" arity="1" since=""/> <fsummary>Read the module version of the BEAM file.</fsummary> <desc> diff --git a/lib/stdlib/doc/src/calendar.xml b/lib/stdlib/doc/src/calendar.xml index 518a085c89..6308420c52 100644 --- a/lib/stdlib/doc/src/calendar.xml +++ b/lib/stdlib/doc/src/calendar.xml @@ -513,7 +513,7 @@ <title>Date and Time Source</title> <p>Local time is obtained from the Erlang BIF <c>localtime/0</c>. Universal time is computed from the BIF <c>universaltime/0</c>.</p> - <p>The following fapply:</p> + <p>The following apply:</p> <list type="bulleted"> <item>There are 86400 seconds in a day.</item> <item>There are 365 days in an ordinary year.</item> diff --git a/lib/stdlib/doc/src/dets.xml b/lib/stdlib/doc/src/dets.xml index 8e4e002000..8b9502a3b1 100644 --- a/lib/stdlib/doc/src/dets.xml +++ b/lib/stdlib/doc/src/dets.xml @@ -1090,8 +1090,8 @@ ok </item> <item> <p><c>select</c> - The table is traversed by calling - <seealso marker="dets:select/3"><c>dets:select/3</c></seealso> and - <seealso marker="dets:select/1"><c>dets:select/1</c></seealso>. + <seealso marker="dets#select/3"><c>dets:select/3</c></seealso> and + <seealso marker="dets#select/1"><c>dets:select/1</c></seealso>. Option <c>n_objects</c> determines the number of objects returned (the third argument of <c>select/3</c>). The match specification (the second argument of diff --git a/lib/stdlib/doc/src/digraph_utils.xml b/lib/stdlib/doc/src/digraph_utils.xml index 13b0aaad9e..a23b02c6c1 100644 --- a/lib/stdlib/doc/src/digraph_utils.xml +++ b/lib/stdlib/doc/src/digraph_utils.xml @@ -371,7 +371,7 @@ the default, the type of <c><anno>Digraph</anno></c> is used for the subgraph as well. Otherwise the option value of <c>type</c> is used as argument to - <seealso marker="digraph:new/1"><c>digraph:new/1</c></seealso>.</p> + <seealso marker="digraph#new/1"><c>digraph:new/1</c></seealso>.</p> <p>If the value of option <c>keep_labels</c> is <c>true</c>, which is the default, the <seealso marker="#label">labels</seealso> of vertices and edges diff --git a/lib/stdlib/doc/src/erl_pp.xml b/lib/stdlib/doc/src/erl_pp.xml index f1c3aa5a41..0a46139db6 100644 --- a/lib/stdlib/doc/src/erl_pp.xml +++ b/lib/stdlib/doc/src/erl_pp.xml @@ -5,7 +5,7 @@ <header> <copyright> <year>1996</year> - <year>2016</year> + <year>2019</year> <holder>Ericsson AB, All Rights Reserved</holder> </copyright> <legalnotice> @@ -65,6 +65,10 @@ </datatype> <datatype> <name name="option"/> + <desc> + <p>The option <c>quote_singleton_atom_types</c> + is used to add quotes to all singleton atom types.</p> + </desc> </datatype> <datatype> <name name="options"/> diff --git a/lib/stdlib/doc/src/ets.xml b/lib/stdlib/doc/src/ets.xml index b9ceaa1d69..2cb677785d 100644 --- a/lib/stdlib/doc/src/ets.xml +++ b/lib/stdlib/doc/src/ets.xml @@ -188,6 +188,31 @@ is used to keep the table fixated during the entire traversal.</p> </item> </list> + <note> + <p>Even though the access of a single object is always guaranteed to be + <seealso marker="#concurrency">atomic and isolated</seealso>, each traversal + through a table to find the next key is not done with such guarantees. This is often + not a problem, but may cause rare subtle "unexpected" effects if a concurrent + process inserts objects during a traversal. For example, consider one + process doing</p> +<pre> +ets:new(t, [ordered_set, named_table]), +ets:insert(t, {1}), +ets:insert(t, {2}), +ets:insert(t, {3}), +</pre> + <p>A concurrent call to <c>ets:first(t)</c>, done by another + process, may then in rare cases return <c>2</c> even though + <c>2</c> has never existed in the table ordered as the first key. In + the same way, a concurrent call to <c>ets:next(t, 1)</c> may return + <c>3</c> even though <c>3</c> never existed in the table + ordered directly after <c>1</c>.</p> + <p>Effects like this are improbable but possible. The probability will + further be reduced (if not vanish) if table option + <seealso marker="#new_2_write_concurrency"><c>write_concurrency</c></seealso> + is not enabled. This can also only be a potential concern for + <c>ordered_set</c> where the traversal order is defined.</p> + </note> <p>Traversals using <c>match</c> and <c>select</c> functions may not need to scan the entire table depending on how the key is specified. A match pattern with a <em>fully bound key</em> (without any match variables) will @@ -617,12 +642,11 @@ Error: fun containing local Erlang function calls <p><marker id="info_2_safe_fixed_monotonic_time"/></p> <p><c>Item=safe_fixed|safe_fixed_monotonic_time, Value={FixationTime,Info}|false</c></p> - <p>If the table has been fixed using + <p>If the table is fixed using <seealso marker="#safe_fixtable/2"> <c>safe_fixtable/2</c></seealso>, the call returns a tuple where <c>FixationTime</c> is the - time when the table was first fixed by a process, which either - is or is not one of the processes it is fixed by now.</p> + last time when the table changed from unfixed to fixed.</p> <p>The format and value of <c>FixationTime</c> depends on <c>Item</c>:</p> <taglist> @@ -654,14 +678,20 @@ Error: fun containing local Erlang function calls table is fixed by now. <c>RefCount</c> is the value of the reference counter and it keeps track of how many times the table has been fixed by the process.</p> - <p>If the table never has been fixed, the call returns - <c>false</c>.</p> + <p>Table fixations are not limited to <seealso marker="#safe_fixtable/2"> + <c>safe_fixtable/2</c></seealso>. Temporary fixations may also + be done by for example <seealso marker="#traversal">traversing + functions</seealso> like <c>select</c> and <c>match</c>. Such + table fixations are automatically released before the + corresponding functions returns, but they may be seen by a + concurrent call to + <c>ets:info(T,safe_fixed|safe_fixed_monotonic_time)</c>.</p> + <p>If the table is not fixed at all, the call returns <c>false</c>.</p> </item> <item> <p><c>Item=stats, Value=tuple()</c></p> - <p>Returns internal statistics about <c>set</c>, <c>bag</c>, and - <c>duplicate_bag</c> tables on an internal format used by OTP - test suites. Not for production use.</p></item> + <p>Returns internal statistics about tables on an internal format + used by OTP test suites. Not for production use.</p></item> </list> </desc> </func> @@ -1190,11 +1220,17 @@ ets:select(Table, MatchSpec),</code> Functions that makes such promises over many objects (like <seealso marker="#insert/2"><c>insert/2</c></seealso>) gain less (or nothing) from this option.</p> - <p>Table type <c>ordered_set</c> is not affected by this option. - Also, the memory consumption inflicted by - both <c>write_concurrency</c> and <c>read_concurrency</c> is a - constant overhead per table. This overhead can be especially - large when both options are combined.</p> + <p>The memory consumption inflicted by both <c>write_concurrency</c> + and <c>read_concurrency</c> is a constant overhead per table for + <c>set</c>, <c>bag</c> and <c>duplicate_bag</c>. For + <c>ordered_set</c> the memory overhead depends on the number + of inserted objects and the amount of actual detected + concurrency in runtime. The memory overhead can be especially + large when both options are combined.</p> + <note> + <p>Prior to stdlib-3.7 (OTP-22.0) <c>write_concurrency</c> had no + effect on <c>ordered_set</c>.</p> + </note> <marker id="new_2_read_concurrency"></marker> </item> <tag><c>{read_concurrency,boolean()}</c></tag> diff --git a/lib/stdlib/doc/src/filename.xml b/lib/stdlib/doc/src/filename.xml index ae42846c6b..60b7eb3436 100644 --- a/lib/stdlib/doc/src/filename.xml +++ b/lib/stdlib/doc/src/filename.xml @@ -546,7 +546,7 @@ true <p><em>Examples:</em></p> <pre> 20> <input>filename:rootname("/beam.src/kalle").</input> -/beam.src/kalle" +"/beam.src/kalle" 21> <input>filename:rootname("/beam.src/foo.erl").</input> "/beam.src/foo" 22> <input>filename:rootname("/beam.src/foo.erl", ".erl").</input> diff --git a/lib/stdlib/doc/src/gen_statem.xml b/lib/stdlib/doc/src/gen_statem.xml index aaa26df18d..6f6849a19d 100644 --- a/lib/stdlib/doc/src/gen_statem.xml +++ b/lib/stdlib/doc/src/gen_statem.xml @@ -4,7 +4,7 @@ <erlref> <header> <copyright> - <year>2016</year><year>2018</year> + <year>2016</year><year>2019</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -167,7 +167,7 @@ erlang:'!' -----> Module:StateName/3 </p> <marker id="state callback"/> <p> - The "<em>state callback</em>" for a specific + The <em>state callback</em> for a specific <seealso marker="#type-state">state</seealso> in a <c>gen_statem</c> is the callback function that is called for all events in this state. It is selected depending on which @@ -179,7 +179,7 @@ erlang:'!' -----> Module:StateName/3 When the <seealso marker="#type-callback_mode"><em>callback mode</em></seealso> is <c>state_functions</c>, the state must be an atom and - is used as the state callback name; see + is used as the <em>state callback</em> name; see <seealso marker="#Module:StateName/3"><c>Module:StateName/3</c></seealso>. This co-locates all code for a specific state in one function as the <c>gen_statem</c> engine @@ -192,7 +192,7 @@ erlang:'!' -----> Module:StateName/3 When the <seealso marker="#type-callback_mode"><em>callback mode</em></seealso> is <c>handle_event_function</c>, the state can be any term - and the state callback name is + and the <em>state callback</em> name is <seealso marker="#Module:handle_event/4"><c>Module:handle_event/4</c></seealso>. This makes it easy to branch depending on state or event as you desire. Be careful about which events you handle in which @@ -200,12 +200,36 @@ erlang:'!' -----> Module:StateName/3 forever creating an infinite busy loop. </p> <p> - The <c>gen_statem</c> enqueues incoming events in order of arrival - and presents these to the - <seealso marker="#state callback">state callback</seealso> - in that order. The state callback can postpone an event - so it is not retried in the current state. - After a state change the queue restarts with the postponed events. + When <c>gen_statem</c> receives a process message it is + converted into an event and the + <seealso marker="#state callback"><em>state callback</em></seealso> + is called with the event as two arguments: type and content. + When the + <seealso marker="#state callback"><em>state callback</em></seealso> + has processed the event it returns to <c>gen_statem</c> + which does a <em>state transition</em>. + If this <em>state transition</em> is to a different state, + that is: <c>NextState =/= State</c>, it is a <em>state change</em>. + </p> + <p> + The + <seealso marker="#state callback"><em>state callback</em></seealso> + may return + <seealso marker="#type-action"><em>transition actions</em></seealso> + for <c>gen_statem</c> + to execute during the <em>state transition</em>, + for example to reply to a + <seealso marker="#call/2"><c>gen_statem:call/2,3</c></seealso>. + </p> + <p> + One of the possible <em>transition actions</em> + is to postpone the current event. + Then it is not retried in the current state. + The <c>gen_statem</c> engine keeps a queue of events + divided into the postponed events + and the events still to process. + After a <em>state change</em> the queue restarts + with the postponed events. </p> <p> The <c>gen_statem</c> event queue model is sufficient @@ -215,13 +239,17 @@ erlang:'!' -----> Module:StateName/3 to entering a new receive statement. </p> <p> - The <seealso marker="#state callback">state callback</seealso> + The + <seealso marker="#state callback"><em>state callback</em></seealso> can insert events using the - <seealso marker="#type-action"><c>action()</c></seealso> + <seealso marker="#type-action"><em>transition actions</em></seealso> <c>next_event</c> - and such an event is inserted as the next to present - to the state callback. That is, as if it is - the oldest incoming event. A dedicated + and such an event is inserted in the event queue + as the next to call the + <seealso marker="#state callback"><em>state callback</em></seealso> + with. + That is, as if it is the oldest incoming event. + A dedicated <seealso marker="#type-event_type"><c>event_type()</c></seealso> <c>internal</c> can be used for such events making them impossible to mistake for external events. @@ -236,24 +264,26 @@ erlang:'!' -----> Module:StateName/3 <p> The <c>gen_statem</c> engine can automatically make a specialized call to the - <seealso marker="#state callback">state callback</seealso> + <seealso marker="#state callback"><em>state callback</em></seealso> whenever a new state is entered; see <seealso marker="#type-state_enter"><c>state_enter()</c></seealso>. This is for writing code common to all state entries. - Another way to do it is to insert an event at the state transition, - and/or to use a dedicated state transition function, + Another way to do it is to explicitly insert an event + at the <em>state transition</em>, + and/or to use a dedicated <em>state transition</em> function, but that is something you will have to remember - at every state transition to the state(s) that need it. + at every <em>state transition</em> to the state(s) that need it. </p> <note> <p>If you in <c>gen_statem</c>, for example, postpone - an event in one state and then call another state callback - of yours, you have not changed states and hence the postponed event - is not retried, which is logical but can be confusing. + an event in one state and then call another <em>state callback</em> + of yours, you have not done a <em>state change</em> + and hence the postponed event is not retried, + which is logical but can be confusing. </p> </note> <p> - For the details of a state transition, see type + For the details of a <em>state transition</em>, see type <seealso marker="#type-transition_option"><c>transition_option()</c></seealso>. </p> <p> @@ -276,7 +306,8 @@ erlang:'!' -----> Module:StateName/3 The <c>gen_statem</c> process can go into hibernation; see <seealso marker="proc_lib#hibernate/3"><c>proc_lib:hibernate/3</c></seealso>. It is done when a - <seealso marker="#state callback">state callback</seealso> or + <seealso marker="#state callback"><em>state callback</em></seealso> + or <seealso marker="#Module:init/1"><c>Module:init/1</c></seealso> specifies <c>hibernate</c> in the returned <seealso marker="#type-action"><c>Actions</c></seealso> @@ -289,12 +320,13 @@ erlang:'!' -----> Module:StateName/3 </p> <p> There is also a server start option - <seealso marker="#type-hibernate_after_opt"> + <seealso marker="#type-enter_loop_opt"> <c>{hibernate_after, Timeout}</c> </seealso> for - <seealso marker="#start/3"><c>start/3,4</c></seealso> or - <seealso marker="#start_link/3"><c>start_link/3,4</c></seealso> + <seealso marker="#start/3"><c>start/3,4</c></seealso>, + <seealso marker="#start_link/3"><c>start_link/3,4</c></seealso> or + <seealso marker="#enter_loop/4"><c>enter_loop/4,5,6</c></seealso>, that may be used to automatically hibernate the server. </p> </description> @@ -483,36 +515,6 @@ handle_event(_, _, State, Data) -> </desc> </datatype> <datatype> - <name name="debug_opt"/> - <desc> - <p> - Debug option that can be used when starting - a <c>gen_statem</c> server through, - <seealso marker="#enter_loop/4"><c>enter_loop/4-6</c></seealso>. - </p> - <p> - For every entry in <c><anno>Dbgs</anno></c>, - the corresponding function in - <seealso marker="sys"><c>sys</c></seealso> is called. - </p> - </desc> - </datatype> - <datatype> - <name name="hibernate_after_opt"/> - <desc> - <p> - hibernate_after option that can be used when starting - a <c>gen_statem</c> server through, - <seealso marker="#enter_loop/4"><c>enter_loop/4-6</c></seealso>. - </p> - <p>If option<seealso marker="#type-hibernate_after_opt"><c>{hibernate_after,HibernateAfterTimeout}</c></seealso> is present, the <c>gen_statem</c> - process awaits any message for <c>HibernateAfterTimeout</c> milliseconds and - if no message is received, the process goes into hibernation automatically - (by calling <seealso marker="proc_lib#hibernate/3"><c>proc_lib:hibernate/3</c></seealso>). - </p> - </desc> - </datatype> - <datatype> <name name="start_opt"/> <desc> <p> @@ -532,6 +534,37 @@ handle_event(_, _, State, Data) -> </desc> </datatype> <datatype> + <name name="enter_loop_opt"/> + <desc> + <p> + Options that can be used when starting + a <c>gen_statem</c> server through, + <seealso marker="#enter_loop/4"><c>enter_loop/4-6</c></seealso>. + </p> + <taglist> + <tag><c>hibernate_after</c></tag> + <item> + <p> + <c>HibernateAfterTimeout</c> + specifies that the <c>gen_statem</c> process awaits + any message for <c>HibernateAfterTimeout</c> milliseconds and + if no message is received, the process goes into hibernation + automatically (by calling + <seealso marker="proc_lib#hibernate/3"><c>proc_lib:hibernate/3</c></seealso>). + </p> + </item> + <tag><c>debug</c></tag> + <item> + <p> + For every entry in <c><anno>Dbgs</anno></c>, + the corresponding function in + <seealso marker="sys"><c>sys</c></seealso> is called. + </p> + </item> + </taglist> + </desc> + </datatype> + <datatype> <name name="from"/> <desc> <p> @@ -551,7 +584,7 @@ handle_event(_, _, State, Data) -> <seealso marker="#type-callback_mode"><em>callback mode</em></seealso> is <c>handle_event_function</c>, the state can be any term. - After a state change (<c>NextState =/= State</c>), + After a <em>state change</em> (<c>NextState =/= State</c>), all postponed events are retried. </p> </desc> @@ -564,7 +597,7 @@ handle_event(_, _, State, Data) -> <seealso marker="#type-callback_mode"><em>callback mode</em></seealso> is <c>state_functions</c>, the state must be of this type. - After a state change (<c>NextState =/= State</c>), + After a <em>state change</em> (<c>NextState =/= State</c>), all postponed events are retried. </p> </desc> @@ -595,7 +628,7 @@ handle_event(_, _, State, Data) -> </p> <p> <c>internal</c> events can only be generated by the - state machine itself through the state transition action + state machine itself through the <em>transition action</em> <seealso marker="#type-action"><c>next_event</c></seealso>. </p> </desc> @@ -633,9 +666,9 @@ handle_event(_, _, State, Data) -> This is the return type from <seealso marker="#Module:callback_mode/0"><c>Module:callback_mode/0</c></seealso> and selects - <seealso marker="#type-callback_mode">callback mode</seealso> + <seealso marker="#type-callback_mode"><em>callback mode</em></seealso> and whether to do - <seealso marker="#type-state_enter">state enter calls</seealso>, + <seealso marker="#type-state_enter"><em>state enter calls</em></seealso>, or not. </p> </desc> @@ -684,13 +717,15 @@ handle_event(_, _, State, Data) -> If <seealso marker="#Module:callback_mode/0"><c>Module:callback_mode/0</c></seealso> returns a list containing <c>state_enter</c>, - the <c>gen_statem</c> engine will, at every state change, + the <c>gen_statem</c> engine will, at every <em>state change</em>, call the <seealso marker="#state callback">state callback</seealso> with arguments <c>(enter, OldState, Data)</c>. This may look like an event but is really a call - performed after the previous state callback returned - and before any event is delivered to the new state callback. + performed after the previous + <seealso marker="#state callback"><em>state callback</em></seealso> + returned and before any event is delivered to the new + <seealso marker="#state callback"><em>state callback</em></seealso>. See <seealso marker="#Module:StateName/3"><c>Module:StateName/3</c></seealso> and @@ -703,27 +738,27 @@ handle_event(_, _, State, Data) -> <seealso marker="#type-state_callback_result"> <c>repeat_state_and_data</c> </seealso> - tuple from the state callback. + tuple from the <em>state callback</em>. </p> <p> If <seealso marker="#Module:callback_mode/0"><c>Module:callback_mode/0</c></seealso> - does not return such a list, no state enter calls are done. + does not return such a list, no <em>state enter calls</em> are done. </p> <p> If <seealso marker="#Module:code_change/4"><c>Module:code_change/4</c></seealso> should transform the state, - it is regarded as a state rename and not a state change, - which will not cause a state enter call. + it is regarded as a state rename and not a <em>state change</em>, + which will not cause a <em>state enter call</em>. </p> <p> - Note that a state enter call <em>will</em> be done + Note that a <em>state enter call</em> <em>will</em> be done right before entering the initial state even though this - formally is not a state change. - In this case <c>OldState</c> will be the same as <c>State</c>, - which can not happen for a subsequent state change, - but will happen when repeating the state enter call. + actually is not a <em>state change</em>. + In this case <c>OldState =:= State</c>, + which cannot happen for a subsequent state change, + but will happen when repeating the <em>state enter call</em>. </p> </desc> </datatype> @@ -733,8 +768,11 @@ handle_event(_, _, State, Data) -> <p> Transition options can be set by <seealso marker="#type-action">actions</seealso> - and modify the state transition. - Here are the sequence of steps for a state transition: + and modify the <em>state transition</em>. + The <em>state transition</em> takes place when the + <seealso marker="#state callback"><em>state callback</em></seealso> + has processed an event and returns. + Here are the sequence of steps for a <em>state transition</em>: </p> <list type="ordered"> <item> @@ -765,7 +803,7 @@ handle_event(_, _, State, Data) -> returned by the state callback that caused the state entry. </p> <p> - Should this state enter call return any of + Should this <em>state enter call</em> return any of the mentioned <c>repeat_*</c> callback results it is repeated again, with the updated <c>Data</c>. </p> @@ -787,7 +825,8 @@ handle_event(_, _, State, Data) -> </item> <item> <p> - If the state changes, the queue of incoming events + If this is a <em>state change</em>, + the queue of incoming events is reset to start with the oldest postponed. </p> </item> @@ -821,7 +860,7 @@ handle_event(_, _, State, Data) -> if the event queue is empty. </p> <p> - A state change cancels a + A <em>state change</em> cancels a <seealso marker="#type-state_timeout"><c>state_timeout()</c></seealso> and any new transition option of this type belongs to the new state. @@ -830,7 +869,7 @@ handle_event(_, _, State, Data) -> <item> <p> If there are enqueued events the - <seealso marker="#state callback">state callback</seealso> + <seealso marker="#state callback"><em>state callback</em></seealso> for the possibly new state is called with the oldest enqueued event, and we start again from the top of this list. @@ -848,7 +887,7 @@ handle_event(_, _, State, Data) -> the next incoming message awakens the <c>gen_statem</c>, but if it is a system event it goes right back into hibernation. When a new message arrives the - <seealso marker="#state callback">state callback</seealso> + <seealso marker="#state callback"><em>state callback</em></seealso> is called with the corresponding event, and we start again from the top of this sequence. </p> @@ -861,7 +900,7 @@ handle_event(_, _, State, Data) -> <desc> <p> If <c>true</c>, postpones the current event and retries - it when the state changes + it after a <em>state change</em> (<c>NextState =/= State</c>). </p> </desc> @@ -1021,9 +1060,9 @@ handle_event(_, _, State, Data) -> <name name="action"/> <desc> <p> - These state transition actions can be invoked by + These <em>transition actions</em> can be invoked by returning them from the - <seealso marker="#state callback">state callback</seealso> + <seealso marker="#state callback"><em>state callback</em></seealso> when it is called with an <seealso marker="#type-event_type">event</seealso>, from @@ -1054,7 +1093,7 @@ handle_event(_, _, State, Data) -> <c>transition_option()</c> </seealso> <seealso marker="#type-postpone"><c>postpone()</c></seealso> - for this state transition. + for this <em>state transition</em>. This action is ignored when returned from <seealso marker="#Module:init/1"><c>Module:init/1</c></seealso> or given to @@ -1093,9 +1132,9 @@ handle_event(_, _, State, Data) -> <name name="enter_action"/> <desc> <p> - These state transition actions can be invoked by + These <em>transition actions</em> can be invoked by returning them from the - <seealso marker="#state callback">state callback</seealso>, from + <seealso marker="#state callback"><em>state callback</em></seealso>, from <seealso marker="#Module:init/1"><c>Module:init/1</c></seealso> or by giving them to <seealso marker="#enter_loop/5"><c>enter_loop/5,6</c></seealso>. @@ -1119,7 +1158,7 @@ handle_event(_, _, State, Data) -> Sets the <seealso marker="#type-transition_option"><c>transition_option()</c></seealso> <seealso marker="#type-hibernate"><c>hibernate()</c></seealso> - for this state transition. + for this <em>state transition</em>. </p> </item> </taglist> @@ -1129,9 +1168,9 @@ handle_event(_, _, State, Data) -> <name name="timeout_action"/> <desc> <p> - These state transition actions can be invoked by + These <em>transition actions</em> can be invoked by returning them from the - <seealso marker="#state callback">state callback</seealso>, from + <seealso marker="#state callback"><em>state callback</em></seealso>, from <seealso marker="#Module:init/1"><c>Module:init/1</c></seealso> or by giving them to <seealso marker="#enter_loop/5"><c>enter_loop/5,6</c></seealso>. @@ -1147,7 +1186,7 @@ handle_event(_, _, State, Data) -> Short for <c>{timeout,Time,Time}</c>, that is, the time-out message is the time-out time. This form exists to make the - <seealso marker="#state callback">state callback</seealso> + <seealso marker="#state callback"><em>state callback</em></seealso> return value <c>{next_state,NextState,NewData,Time}</c> allowed like for <c>gen_fsm</c>. </p> @@ -1193,9 +1232,9 @@ handle_event(_, _, State, Data) -> <name name="reply_action"/> <desc> <p> - This state transition action can be invoked by + This <em>transition action</em> can be invoked by returning it from the - <seealso marker="#state callback">state callback</seealso>, from + <seealso marker="#state callback"><em>state callback</em></seealso>, from <seealso marker="#Module:init/1"><c>Module:init/1</c></seealso> or by giving it to <seealso marker="#enter_loop/5"><c>enter_loop/5,6</c></seealso>. @@ -1210,7 +1249,7 @@ handle_event(_, _, State, Data) -> <c><anno>From</anno></c> must be the term from argument <seealso marker="#type-event_type"><c>{call,<anno>From</anno>}</c></seealso> in a call to a - <seealso marker="#state callback">state callback</seealso>. + <seealso marker="#state callback"><em>state callback</em></seealso>. </p> <p> Note that using this action from @@ -1219,7 +1258,7 @@ handle_event(_, _, State, Data) -> <seealso marker="#enter_loop/5"><c>enter_loop/5,6</c></seealso> would be weird on the border of witchcraft since there has been no earlier call to a - <seealso marker="#state callback">state callback</seealso> + <seealso marker="#state callback"><em>state callback</em></seealso> in this server. </p> </desc> @@ -1239,7 +1278,7 @@ handle_event(_, _, State, Data) -> The <seealso marker="#type-action"><c>Actions</c></seealso> are executed when entering the first <seealso marker="#type-state">state</seealso> just as for a - <seealso marker="#state callback">state callback</seealso>, + <seealso marker="#state callback"><em>state callback</em></seealso>, except that the action <c>postpone</c> is forced to <c>false</c> since there is no event to postpone. </p> @@ -1256,7 +1295,7 @@ handle_event(_, _, State, Data) -> <desc> <p> <c><anno>State</anno></c> is the current state - and it can not be changed since the state callback + and it cannot be changed since the state callback was called with a <seealso marker="#type-state_enter"><em>state enter call</em></seealso>. </p> @@ -1292,11 +1331,13 @@ handle_event(_, _, State, Data) -> <tag><c>next_state</c></tag> <item> <p> - The <c>gen_statem</c> does a state transition to + The <c>gen_statem</c> does a <em>state transition</em> to <c><anno>NextState</anno></c> (which can be the same as the current state), sets <c><anno>NewData</anno></c>, and executes all <c><anno>Actions</anno></c>. + If <c><anno>NextState</anno> =/= CurrentState</c> + the <em>state transition</em> is a <em>state change</em>. </p> </item> </taglist> @@ -1318,54 +1359,33 @@ handle_event(_, _, State, Data) -> <tag><c>keep_state</c></tag> <item> <p> - The <c>gen_statem</c> keeps the current state, or - does a state transition to the current state if you like, - sets <c><anno>NewData</anno></c>, - and executes all <c><anno>Actions</anno></c>. - This is the same as + The same as <c>{next_state,CurrentState,<anno>NewData</anno>,<anno>Actions</anno>}</c>. </p> </item> <tag><c>keep_state_and_data</c></tag> <item> <p> - The <c>gen_statem</c> keeps the current state or - does a state transition to the current state if you like, - keeps the current server data, - and executes all <c><anno>Actions</anno></c>. - This is the same as - <c>{next_state,CurrentState,CurrentData,<anno>Actions</anno>}</c>. + The same as + <c>{keep_state,CurrentData,<anno>Actions</anno>}</c>. </p> </item> <tag><c>repeat_state</c></tag> <item> <p> - The <c>gen_statem</c> keeps the current state, or - does a state transition to the current state if you like, - sets <c><anno>NewData</anno></c>, - and executes all <c><anno>Actions</anno></c>. If the <c>gen_statem</c> runs with <seealso marker="#type-state_enter"><em>state enter calls</em></seealso>, - the state enter call is repeated, see type + the <em>state enter call</em> is repeated, see type <seealso marker="#type-transition_option"><c>transition_option()</c></seealso>, - otherwise <c>repeat_state</c> is the same as + other than that <c>repeat_state</c> is the same as <c>keep_state</c>. </p> </item> <tag><c>repeat_state_and_data</c></tag> <item> <p> - The <c>gen_statem</c> keeps the current state and data, or - does a state transition to the current state if you like, - and executes all <c><anno>Actions</anno></c>. - This is the same as + The same as <c>{repeat_state,CurrentData,<anno>Actions</anno>}</c>. - If the <c>gen_statem</c> runs with - <seealso marker="#type-state_enter"><em>state enter calls</em></seealso>, - the state enter call is repeated, see type - <seealso marker="#type-transition_option"><c>transition_option()</c></seealso>, - otherwise <c>repeat_state_and_data</c> is the same as - <c>keep_state_and_data</c>. </p> </item> <tag><c>stop</c></tag> @@ -1408,14 +1428,15 @@ handle_event(_, _, State, Data) -> by sending a request and waiting until its reply arrives. The <c>gen_statem</c> calls the - <seealso marker="#state callback">state callback</seealso> with + <seealso marker="#state callback"><em>state callback</em></seealso> + with <seealso marker="#type-event_type"><c>event_type()</c></seealso> <c>{call,From}</c> and event content <c><anno>Request</anno></c>. </p> <p> A <c><anno>Reply</anno></c> is generated when a - <seealso marker="#state callback">state callback</seealso> + <seealso marker="#state callback"><em>state callback</em></seealso> returns with <c>{reply,From,<anno>Reply</anno>}</c> as one <seealso marker="#type-action"><c>action()</c></seealso>, @@ -1484,7 +1505,8 @@ handle_event(_, _, State, Data) -> ignoring if the destination node or <c>gen_statem</c> does not exist. The <c>gen_statem</c> calls the - <seealso marker="#state callback">state callback</seealso> with + <seealso marker="#state callback"><em>state callback</em></seealso> + with <seealso marker="#type-event_type"><c>event_type()</c></seealso> <c>cast</c> and event content <c><anno>Msg</anno></c>. @@ -1598,18 +1620,18 @@ handle_event(_, _, State, Data) -> <seealso marker="#call/2"><c>call/2</c></seealso> when the reply cannot be defined in the return value of a - <seealso marker="#state callback">state callback</seealso>. + <seealso marker="#state callback"><em>state callback</em></seealso>. </p> <p> <c><anno>From</anno></c> must be the term from argument <seealso marker="#type-event_type"><c>{call,<anno>From</anno>}</c></seealso> to the - <seealso marker="#state callback">state callback</seealso>. + <seealso marker="#state callback"><em>state callback</em></seealso>. A reply or multiple replies canalso be sent using one or several <seealso marker="#type-reply_action"><c>reply_action()</c></seealso>s from a - <seealso marker="#state callback">state callback</seealso>. + <seealso marker="#state callback"><em>state callback</em></seealso>. </p> <note> <p> @@ -1681,7 +1703,11 @@ handle_event(_, _, State, Data) -> <list type="bulleted"> <item> <p> - If option <c>{timeout,Time}</c> is present in + If option + <seealso marker="#type-start_opt"> + <c>{timeout,Time}</c> + </seealso> + is present in <c><anno>Opts</anno></c>, the <c>gen_statem</c> is allowed to spend <c>Time</c> milliseconds initializing or it terminates and the start function returns @@ -1689,23 +1715,33 @@ handle_event(_, _, State, Data) -> </p> </item> <item> - <p>If option<seealso marker="#type-hibernate_after_opt"><c>{hibernate_after,HibernateAfterTimeout}</c></seealso> is present, the <c>gen_statem</c> - process awaits any message for <c>HibernateAfterTimeout</c> milliseconds and - if no message is received, the process goes into hibernation automatically - (by calling <seealso marker="proc_lib#hibernate/3"><c>proc_lib:hibernate/3</c></seealso>). + <p>If option + <seealso marker="#type-enter_loop_opt"> + <c>{hibernate_after,HibernateAfterTimeout}</c> + </seealso> + is present, the <c>gen_statem</c> + process awaits any message for <c>HibernateAfterTimeout</c> milliseconds and + if no message is received, the process goes into hibernation automatically + (by calling <seealso marker="proc_lib#hibernate/3"><c>proc_lib:hibernate/3</c></seealso>). </p> </item> <item> <p> If option - <seealso marker="#type-debug_opt"><c>{debug,Dbgs}</c></seealso> + <seealso marker="#type-enter_loop_opt"> + <c>{debug,Dbgs}</c> + </seealso> is present in <c><anno>Opts</anno></c>, debugging through <seealso marker="sys"><c>sys</c></seealso> is activated. </p> </item> <item> <p> - If option <c>{spawn_opt,SpawnOpts}</c> is present in + If option + <seealso marker="#type-start_opt"> + <c>{spawn_opt,SpawnOpts}</c> + </seealso> + is present in <c><anno>Opts</anno></c>, <c>SpawnOpts</c> is passed as option list to <seealso marker="erts:erlang#spawn_opt/2"><c>erlang:spawn_opt/2</c></seealso>, @@ -1826,7 +1862,7 @@ handle_event(_, _, State, Data) -> for efficiency reasons, so this function is only called once after server start and after code change, but before the first - <seealso marker="#state callback">state callback</seealso> + <seealso marker="#state callback"><em>state callback</em></seealso> in the current code version is called. More occasions may be added in future versions of <c>gen_statem</c>. @@ -1883,7 +1919,7 @@ handle_event(_, _, State, Data) -> <p> This callback is optional, so callback modules need not export it. If a release upgrade/downgrade with - <c>Change={advanced,Extra}</c> + <c>Change = {advanced,Extra}</c> specified in the <c>.appup</c> file is made when <c>code_change/4</c> is not implemented the process will crash with exit reason <c>undef</c>. @@ -1893,7 +1929,7 @@ handle_event(_, _, State, Data) -> This function is called by a <c>gen_statem</c> when it is to update its internal state during a release upgrade/downgrade, that is, when the instruction <c>{update,Module,Change,...}</c>, - where <c>Change={advanced,Extra}</c>, is specified in the + where <c>Change = {advanced,Extra}</c>, is specified in the <seealso marker="sasl:appup"><c>appup</c></seealso> file. For more information, see <seealso marker="doc/design_principles:release_handling#instr">OTP Design Principles</seealso>. @@ -1922,7 +1958,7 @@ handle_event(_, _, State, Data) -> <p> If the function returns a failure <c>Reason</c>, the ongoing upgrade fails and rolls back to the old release. - Note that <c>Reason</c> can not be an <c>{ok,_,_}</c> tuple + Note that <c>Reason</c> cannot be an <c>{ok,_,_}</c> tuple since that will be regarded as a <c>{ok,NewState,NewData}</c> tuple, and that a tuple matching <c>{ok,_}</c> @@ -1933,13 +1969,13 @@ handle_event(_, _, State, Data) -> <p> Also note when upgrading a <c>gen_statem</c>, this function and hence - the <c>Change={advanced,Extra}</c> parameter in the + the <c>Change = {advanced,Extra}</c> parameter in the <seealso marker="sasl:appup"><c>appup</c></seealso> file is not only needed to update the internal state or to act on the <c>Extra</c> argument. It is also needed if an upgrade or downgrade should change <seealso marker="#type-callback_mode"><em>callback mode</em></seealso>, - or else the callback mode after the code change + or else the <em>callback mode</em> after the code change will not be honoured, most probably causing a server crash. </p> @@ -2148,7 +2184,7 @@ init(Args) -> erlang:error(not_implemented, [Args]).</pre> <seealso marker="#type-event_type"><c>{call,From}</c></seealso>, the caller waits for a reply. The reply can be sent from this or from any other - <seealso marker="#state callback">state callback</seealso> + <seealso marker="#state callback"><em>state callback</em></seealso> by returning with <c>{reply,From,Reply}</c> in <seealso marker="#type-action"><c>Actions</c></seealso>, in <seealso marker="#type-reply_action"><c>Replies</c></seealso>, @@ -2173,9 +2209,9 @@ init(Args) -> erlang:error(not_implemented, [Args]).</pre> </p> <p> When the <c>gen_statem</c> runs with - <seealso marker="#type-state_enter">state enter calls</seealso>, + <seealso marker="#type-state_enter"><em>state enter calls</em></seealso>, these functions are also called with arguments - <c>(enter, OldState, ...)</c> whenever the state changes. + <c>(enter, OldState, ...)</c> during every <em>state change</em>. In this case there are some restrictions on the <seealso marker="#type-enter_action">actions</seealso> that may be returned: @@ -2208,7 +2244,7 @@ init(Args) -> erlang:error(not_implemented, [Args]).</pre> <seealso marker="erts:erlang#throw/1"><c>throw</c></seealso> to return the result, which can be useful. For example to bail out with <c>throw(keep_state_and_data)</c> - from deep within complex code that can not + from deep within complex code that cannot return <c>{next_state,State,Data}</c> because <c>State</c> or <c>Data</c> is no longer in scope. </p> diff --git a/lib/stdlib/doc/src/maps.xml b/lib/stdlib/doc/src/maps.xml index e2a62cb397..8e88882b56 100644 --- a/lib/stdlib/doc/src/maps.xml +++ b/lib/stdlib/doc/src/maps.xml @@ -35,9 +35,10 @@ <datatypes> <datatype> - <name name="iterator"/> + <name name="iterator" n_vars="2"/> <desc> - <p>An iterator representing the key value associations in a map.</p> + <p>An iterator representing the associations in a map with keys of type + <c><anno>Key</anno></c> and values of type <c><anno>Value</anno></c>.</p> <p>Created using <seealso marker="#iterator-1"><c>maps:iterator/1</c></seealso>.</p> <p>Consumed by <seealso marker="#next-1"><c>maps:next/1</c></seealso>, <seealso marker="#filter-2"><c>maps:filter/2</c></seealso>, @@ -45,6 +46,10 @@ <seealso marker="#map-2"><c>maps:map/2</c></seealso>.</p> </desc> </datatype> + + <datatype> + <name name="iterator" n_vars="0"/> + </datatype> </datatypes> <funcs> @@ -90,13 +95,13 @@ <name name="fold" arity="3" since="OTP 17.0"/> <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>MapOrIter</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>Calls <c>F(Key, Value, AccIn)</c> for every <c><anno>Key</anno></c> + to value <c><anno>Value</anno></c> association in + <c><anno>MapOrIter</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>The call fails with a <c>{badmap,Map}</c> exception if <c><anno>MapOrIter</anno></c> is not a map or valid iterator, or with <c>badarg</c> if <c><anno>Fun</anno></c> is not a @@ -234,11 +239,12 @@ none</code> <fsummary></fsummary> <desc> <p>Produces a new map <c><anno>Map</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>MapOrIter</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>Map</anno></c>.</p> + <c>fun F(Key, Value1)</c> for every <c><anno>Key</anno></c> to value + <c><anno>Value1</anno></c> association in + <c><anno>MapOrIter</anno></c> in any order. Function <c>fun Fun/2</c> + must return value <c><anno>Value2</anno></c> to be associated with + key <c><anno>Key</anno></c> for the new map + <c><anno>Map</anno></c>.</p> <p>The call fails with a <c>{badmap,Map}</c> exception if <c><anno>MapOrIter</anno></c> is not a map or valid iterator, or with <c>badarg</c> if <c><anno>Fun</anno></c> is not a diff --git a/lib/stdlib/doc/src/notes.xml b/lib/stdlib/doc/src/notes.xml index f677438154..65650a25c7 100644 --- a/lib/stdlib/doc/src/notes.xml +++ b/lib/stdlib/doc/src/notes.xml @@ -3884,7 +3884,7 @@ you use erlang:halt/2 with an integer first argument and an option list containing {flush,false} as the second argument. Note that now is flushing not dependant of the - exit code, and you can not only flush async threads + exit code, and you cannot only flush async threads operations which we deemed as a strange behaviour anyway. </p> <p>Also, erlang:halt/1,2 has gotten a new feature: If the @@ -4398,9 +4398,9 @@ Supervisors should not save child-specs for temporary processes when they terminate as they should not be restarted. Saving the temporary child spec will result in - that you can not start a new temporary process with the + that you cannot start a new temporary process with the same child spec as an already terminated temporary - process. Since R14B02 you can not restart a temporary + process. Since R14B02 you cannot restart a temporary temporary process as arguments are no longer saved, it has however always been semantically incorrect to restart a temporary process. Thanks to Filipe David Manana for diff --git a/lib/stdlib/doc/src/proc_lib.xml b/lib/stdlib/doc/src/proc_lib.xml index aeb9f48735..bb983903a9 100644 --- a/lib/stdlib/doc/src/proc_lib.xml +++ b/lib/stdlib/doc/src/proc_lib.xml @@ -166,7 +166,7 @@ <fsummary>Hibernate a process until a message is sent to it.</fsummary> <desc> <p>This function does the same as (and does call) the - <seealso marker="erts:erlang#erlang:hibernate/3"> + <seealso marker="erts:erlang#hibernate/3"> <c>hibernate/3</c></seealso> BIF, but ensures that exception handling and logging continues to work as expected when the process wakes up.</p> diff --git a/lib/stdlib/doc/src/qlc.xml b/lib/stdlib/doc/src/qlc.xml index fe60c2e9bb..34f7c5bab9 100644 --- a/lib/stdlib/doc/src/qlc.xml +++ b/lib/stdlib/doc/src/qlc.xml @@ -4,7 +4,7 @@ <erlref> <header> <copyright> - <year>2004</year><year>2016</year> + <year>2004</year><year>2019</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -581,11 +581,13 @@ gb_iter(I0, N, EFun) -> <input>{K} <- ets:table(E1),</input> <input>K == 2.71 orelse K == a]),</input> <input>io:format("~s~n", [qlc:info(Q1)]).</input> -ets:match_spec_run(lists:flatmap(fun(V) -> - ets:lookup(20493, V) - end, - [a,2.71]), - ets:match_spec_compile([{{'$1'},[],['$1']}]))</pre> +ets:match_spec_run( + lists:flatmap(fun(V) -> + ets:lookup(#Ref<0.3098908599.2283929601.256025>, + V) + end, + [a, 2.71]), + ets:match_spec_compile([{{'$1'}, [], ['$1']}]))</pre> <p>In the example, operator <c>==/2</c> has been handled exactly as <c>=:=/2</c> would have been handled. However, @@ -607,9 +609,10 @@ ets:match_spec_run(lists:flatmap(fun(V) -> <input>end,</input> <input>Q2 = F2({2,2}),</input> <input>io:format("~s~n", [qlc:info(Q2)]).</input> -ets:table(53264, +ets:table(#Ref<0.3098908599.2283929601.256125>, [{traverse, - {select,[{{'$1','$2'},[{'==','$1',{const,{2,2}}}],['$2']}]}}]) + {select, + [{{'$1', '$2'}, [{'==', '$1', {const, {2, 2}}}], ['$2']}]}}]) 3> <input>lists:sort(qlc:e(Q2)).</input> [a,b,c]</pre> @@ -629,8 +632,9 @@ ets:table(53264, <input>end,</input> <input>Q3 = F3({2,2}),</input> <input>io:format("~s~n", [qlc:info(Q3)]).</input> -ets:match_spec_run(ets:lookup(86033, {2,2}), - ets:match_spec_compile([{{'$1','$2'},[],['$2']}])) +ets:match_spec_run(ets:lookup(#Ref<0.3098908599.2283929601.256211>, + {2, 2}), + ets:match_spec_compile([{{'$1', '$2'}, [], ['$2']}])) 5> <input>qlc:e(Q3).</input> [b]</pre> @@ -892,21 +896,21 @@ begin V1 = qlc:q([ SQV || - SQV <- [x,y] + SQV <- [x, y] ], - [{unique,true}]), + [{unique, true}]), V2 = qlc:q([ SQV || - SQV <- [a,b] + SQV <- [a, b] ], - [{unique,true}]), + [{unique, true}]), qlc:q([ {X,Y} || X <- V1, Y <- V2 ], - [{unique,true}]) + [{unique, true}]) end</pre> <p>In the following example QLC <c>V2</c> has been inserted to show the joined generators and the join @@ -927,19 +931,21 @@ begin V1 = qlc:q([ P0 || - P0 = {W,Y} <- ets:table(17) + P0 = {W, Y} <- + ets:table(#Ref<0.3098908599.2283929601.256549>) ]), V2 = qlc:q([ - [G1|G2] || + [G1 | G2] || G2 <- V1, - G1 <- ets:table(16), + G1 <- + ets:table(#Ref<0.3098908599.2283929601.256548>), element(2, G1) =:= element(1, G2) ], - [{join,lookup}]), + [{join, lookup}]), qlc:q([ - {X,Z,W} || - [{X,Z}|{W,Y}] <- V2 + {X, Z, W} || + [{X, Z} | {W, Y}] <- V2 ]) end</pre> </desc> @@ -1080,27 +1086,27 @@ begin V1 = qlc:q([ P0 || - P0 = {X,Z} <- - qlc:keysort(1, [{a,1},{b,4},{c,6}], []) + P0 = {X, Z} <- + qlc:keysort(1, [{a, 1}, {b, 4}, {c, 6}], []) ]), V2 = qlc:q([ P0 || - P0 = {W,Y} <- - qlc:keysort(2, [{2,a},{3,b},{4,c}], []) + P0 = {W, Y} <- + qlc:keysort(2, [{2, a}, {3, b}, {4, c}], []) ]), V3 = qlc:q([ - [G1|G2] || + [G1 | G2] || G1 <- V1, G2 <- V2, element(1, G1) == element(2, G2) ], - [{join,merge},{cache,list}]), + [{join, merge}, {cache, list}]), qlc:q([ - {A,X,Z,W} || - A <- [a,b,c], - [{X,Z}|{W,Y}] <- V3, + {A, X, Z, W} || + A <- [a, b, c], + [{X, Z} | {W, Y}] <- V3, X =:= Y ]) end</pre> @@ -1141,14 +1147,21 @@ ets:match_spec_run( gb_trees:lookup(K, gb_trees:from_orddict([])) of - {value,V} -> - [{K,V}]; + {value, V} -> + [{K, V}]; none -> [] end end, - [{1,a},{1,b},{1,c},{2,a},{2,b},{2,c}]), - ets:match_spec_compile([{{{'$1','$2'},'_'},[],['$1']}]))</pre> + [{1, a}, + {1, b}, + {1, c}, + {2, a}, + {2, b}, + {2, c}]), + ets:match_spec_compile([{{{'$1', '$2'}, '_'}, + [], + ['$1']}]))</pre> <p>Options:</p> <list type="bulleted"> <item> diff --git a/lib/stdlib/doc/src/rand.xml b/lib/stdlib/doc/src/rand.xml index 27d2d99f3c..b4737b48f8 100644 --- a/lib/stdlib/doc/src/rand.xml +++ b/lib/stdlib/doc/src/rand.xml @@ -38,25 +38,71 @@ <p> This module provides a pseudo random number generator. The module contains a number of algorithms. - The uniform distribution algorithms use the + The uniform distribution algorithms are based on the <url href="http://xorshift.di.unimi.it"> - xoroshiro116+ and xorshift1024* algorithms by Sebastiano Vigna. + Xoroshiro and Xorshift algorithms </url> + by Sebastiano Vigna. The normal distribution algorithm uses the <url href="http://www.jstatsoft.org/v05/i08"> Ziggurat Method by Marsaglia and Tsang </url> on top of the uniform distribution algorithm. </p> - <p>For some algorithms, jump functions are provided for generating - non-overlapping sequences for parallel computations. - The jump functions perform calculations - equivalent to perform a large number of repeated calls - for calculating new states. </p> + <p> + For most algorithms, jump functions are provided for generating + non-overlapping sequences for parallel computations. + The jump functions perform calculations + equivalent to perform a large number of repeated calls + for calculating new states. + </p> <p>The following algorithms are provided:</p> <taglist> + <tag><c>exsss</c></tag> + <item> + <p>Xorshift116**, 58 bits precision and period of 2^116-1</p> + <p>Jump function: equivalent to 2^64 calls</p> + <p> + This is the Xorshift116 generator combined with the StarStar scrambler + from the 2018 paper by David Blackman and Sebastiano Vigna: + <url href="http://vigna.di.unimi.it/ftp/papers/ScrambledLinear.pdf"> + Scrambled Linear Pseudorandom Number Generators + </url> + </p> + <p> + The generator does not need 58-bit rotates so it is faster + than the Xoroshiro116 generator, and when combined with + the StarStar scrambler it does not have any weak low bits + like <c>exrop</c> (Xoroshiro116+). + </p> + <p> + Alas, this combination is about 10% slower than <c>exrop</c>, + but is despite that the default algorithm thanks to its + statistical qualities. + </p> + </item> + <tag><c>exro928ss</c></tag> + <item> + <p>Xoroshiro928**, 58 bits precision and a period of 2^928-1</p> + <p>Jump function: equivalent to 2^512 calls</p> + <p> + This is a 58 bit version of Xoroshiro1024**, + from the 2018 paper by David Blackman and Sebastiano Vigna: + <url href="http://vigna.di.unimi.it/ftp/papers/ScrambledLinear.pdf"> + Scrambled Linear Pseudorandom Number Generators + </url> + that on a 64 bit Erlang system executes only about 40% slower than + the default <c>exsss</c> algorithm but with much longer period + and better statistical properties, and on the flip side + a larger state. + </p> + <p> + Many thanks to Sebastiano Vigna for his help with + the 58 bit adaption. + </p> + </item> <tag><c>exrop</c></tag> <item> <p>Xoroshiro116+, 58 bits precision and period of 2^116-1</p> @@ -83,7 +129,7 @@ </taglist> <p> - The default algorithm is <c>exrop</c> (Xoroshiro116+). + The default algorithm is <c>exsss</c> (Xorshift116**). If a specific algorithm is required, ensure to always use <seealso marker="#seed-1"> <c>seed/1</c></seealso> to initialize the state. @@ -154,19 +200,19 @@ R1 = rand:uniform(),</pre> <p>Use a specified algorithm:</p> <pre> -_ = rand:seed(exs1024s), +_ = rand:seed(exs928ss), R2 = rand:uniform(),</pre> <p>Use a specified algorithm with a constant seed:</p> <pre> -_ = rand:seed(exs1024s, {123, 123534, 345345}), +_ = rand:seed(exs928ss, {123, 123534, 345345}), R3 = rand:uniform(),</pre> <p>Use the functional API with a non-constant seed:</p> <pre> -S0 = rand:seed_s(exrop), +S0 = rand:seed_s(exsss), {R4, S1} = rand:uniform_s(S0),</pre> <p>Textbook basic form Box-Muller standard normal deviate</p> @@ -195,8 +241,9 @@ SND0 = math:sqrt(-2 * math:log(R5)) * math:cos(math:pi() * R6)</pre> </note> <p> - For all these generators the lowest bit(s) has got - a slightly less random behaviour than all other bits. + For all these generators except <c>exro928ss</c> and <c>exsss</c> + the lowest bit(s) has got a slightly less + random behaviour than all other bits. 1 bit for <c>exrop</c> (and <c>exsp</c>), and 3 bits for <c>exs1024s</c>. See for example the explanation in the @@ -211,7 +258,7 @@ up to (and included) 16TB, with the exception of binary rank tests, which fail due to the lowest bit being an LFSR; all other bits pass all tests. We suggest to use a sign test to extract a random Boolean value.</pre> <p> - If this is a problem; to generate a boolean + If this is a problem; to generate a boolean with these algorithms use something like this: </p> <pre>(rand:uniform(16) > 8)</pre> @@ -254,21 +301,50 @@ tests. We suggest to use a sign test to extract a random Boolean value.</pre> </desc> </datatype> <datatype> - <name name="exs64_state"/> - <desc><p>Algorithm specific internal state</p></desc> + <name name="seed"/> + <desc> + <p> + A seed value for the generator. + </p> + <p> + A list of integers sets the generator's internal state directly, + after algorithm-dependent checks of the value + and masking to the proper word size. + </p> + <p> + An integer is used as the initial state for a SplitMix64 generator. + The output values of that is then used for setting + the generator's internal state + after masking to the proper word size + and if needed avoiding zero values. + </p> + <p> + A traditional 3-tuple of integers seed is passed through + algorithm-dependent hashing functions to create + the generator's initial state. + </p> + </desc> </datatype> <datatype> <name name="exsplus_state"/> <desc><p>Algorithm specific internal state</p></desc> </datatype> <datatype> - <name name="exs1024_state"/> + <name name="exro928_state"/> <desc><p>Algorithm specific internal state</p></desc> </datatype> <datatype> <name name="exrop_state"/> <desc><p>Algorithm specific internal state</p></desc> </datatype> + <datatype> + <name name="exs1024_state"/> + <desc><p>Algorithm specific internal state</p></desc> + </datatype> + <datatype> + <name name="exs64_state"/> + <desc><p>Algorithm specific internal state</p></desc> + </datatype> </datatypes> <funcs> diff --git a/lib/stdlib/doc/src/slave.xml b/lib/stdlib/doc/src/slave.xml index 80fb28b548..f9e42ad47d 100644 --- a/lib/stdlib/doc/src/slave.xml +++ b/lib/stdlib/doc/src/slave.xml @@ -39,23 +39,30 @@ done through the master.</p> <p>Slave nodes on other hosts than the current one are started with - the <c>rsh</c> program. The user must be allowed to <c>rsh</c> to + the <c>ssh</c> program. The user must be allowed to <c>ssh</c> to the remote hosts without being prompted for a password. This can - be arranged in a number of ways (for details, see the <c>rsh</c> + be arranged in a number of ways (for details, see the <c>ssh</c> documentation). A slave node started on the same host as the master inherits certain environment values from the master, such as the current directory and the environment variables. For what can be assumed about the environment when a slave is started - on another host, see the documentation for the <c>rsh</c> + on another host, see the documentation for the <c>ssh</c> program.</p> - <p>An alternative to the <c>rsh</c> program can be specified on + <p>An alternative to the <c>ssh</c> program can be specified on the command line to - <seealso marker="erts:erl#erl"><c>erl(1)</c></seealso> as follows:</p> + <seealso marker="erts:erl"><c>erl(1)</c></seealso> as follows:</p> <pre> -rsh Program</pre> + <p>Note that the command specified with the <c>-rsh</c> flag is + treated as a file name which may contain spaces. It is thus not + possible to include any command line options. The remote node will + be launched as <c>"$RSH" "$REMOTE_HOSTNAME" erl -detached -noinput + ...</c>, so the + <c>erl</c> command must be found in the path on the remote host.</p> + <p>The slave node is to use the same file system at the master. At least, Erlang/OTP is to be installed in the same place on both computers and the same version of Erlang is to be used.</p> @@ -133,7 +140,7 @@ rpc:call(N, slave, pseudo, [node(), [pxw_server]]).</code> <p>Argument <c><anno>Args</anno></c> is used to set <c>erl</c> command-line arguments. If provided, it is passed to the new node and can be used for a variety of purposes; see - <seealso marker="erts:erl#erl"><c>erl(1)</c></seealso>.</p> + <seealso marker="erts:erl"><c>erl(1)</c></seealso>.</p> <p>As an example, suppose that you want to start a slave node at host <c>H</c> with node name <c>Name@H</c> and want the slave node to have the following properties:</p> @@ -166,7 +173,9 @@ slave:start(H, Name, Arg).</code> </item> <tag><c>no_rsh</c></tag> <item> - <p>There is no <c>rsh</c> program on the computer.</p> + <p>No remote shell program was found on the computer. Note + that <c>ssh</c> is used by default, but this can be overridden + with the <c>-rsh</c> flag.</p> </item> <tag><c>{already_running, <anno>Node</anno>}</c></tag> <item> diff --git a/lib/stdlib/doc/src/sys.xml b/lib/stdlib/doc/src/sys.xml index 6fc508b853..e22ca89ef5 100644 --- a/lib/stdlib/doc/src/sys.xml +++ b/lib/stdlib/doc/src/sys.xml @@ -4,7 +4,7 @@ <erlref> <header> <copyright> - <year>1996</year><year>2018</year> + <year>1996</year><year>2019</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -114,6 +114,154 @@ </datatype> <datatype> <name name="system_event"/> + <desc> + <taglist> + <tag><c>{in,<anno>Msg</anno>}</c></tag> + <item> + <p> + Is produced by <c>gen_server</c> and <c>gen_event</c> + when the message <c>Msg</c> arrives. + </p> + </item> + <tag><c>{in,<anno>Msg</anno>,<anno>State</anno>}</c></tag> + <item> + <p> + Is produced by <c>gen_statem</c> + when the message <c>Msg</c> arrives in state <c>State</c>. + </p> + <p> + For <c>gen_statem</c> the <c><anno>Msg</anno></c> term is + an <c>{EventType,EventContent}</c> tuple. + </p> + </item> + <tag><c>{out,<anno>Msg</anno>,<anno>To</anno>}</c></tag> + <item> + <p> + Is produced by <c>gen_statem</c> when the reply <c>Msg</c> + is sent back to <c>To</c> by returning + a <c>{reply,To,Msg}</c> action from the callback module. + </p> + <p> + <c><anno>To</anno></c> is of the same type + as the first argument to <c>gen_statem:reply/2</c>. + </p> + </item> + <tag> + <c>{out,<anno>Msg</anno>,<anno>To</anno>,<anno>State</anno>}</c> + </tag> + <item> + <p> + Is produced by <c>gen_server</c> + when the reply <c><anno>Msg</anno></c> + is sent back to <c><anno>To</anno></c> + by returning a <c>{reply,...}</c> tuple + from the callback module. + </p> + <p> + <c><anno>To</anno></c> is of the same type + as the first argument to <c>gen_server:reply/2</c>. + </p> + <p> + <c><anno>State</anno></c> is the new server state. + </p> + </item> + <tag> + <c>{noreply,<anno>State</anno>}</c> + </tag> + <item> + <p> + Is produced by <c>gen_server</c> + when a <c>{noreply,...}</c> tuple is returned + from the callback module. + </p> + <p> + <c><anno>State</anno></c> is the new server state. + </p> + </item> + <tag> + <c>{continue,<anno>Continuation</anno>}</c> + </tag> + <item> + <p> + Is produced by <c>gen_server</c> + when a <c>{continue,<anno>Continuation</anno>}</c> + tuple is returned from the callback module. + </p> + </item> + <tag> + <c>{code_change,<anno>Event</anno>,<anno>State</anno>}</c> + </tag> + <item> + <p> + Is produced by <c>gen_statem</c> + when the message <c><anno>Event</anno></c> + arrives in state <c><anno>State</anno></c> + as the first event after a code change. + </p> + <p> + <c><anno>Event</anno></c> is + an <c>{EventType,EventContent}</c> tuple. + </p> + </item> + <tag> + <c> + {postpone,<anno>Event</anno>,<anno>State</anno>,<anno>NextState</anno>} + </c> + </tag> + <item> + <p> + Is produced by <c>gen_statem</c> + when the message <c><anno>Event</anno></c> + is postponed in state <c><anno>State</anno></c>. + <c><anno>NextState</anno></c> is the new state. + </p> + <p> + <c><anno>Event</anno></c> is + an <c>{EventType,EventContent}</c> tuple. + </p> + </item> + <tag> + <c> + {consume,<anno>Event</anno>,<anno>State</anno>,<anno>NextState</anno>} + </c> + </tag> + <item> + <p> + Is produced by <c>gen_statem</c> + when the message <c><anno>Event</anno></c> + is consumed in state <c><anno>State</anno></c>. + <c><anno>NextState</anno></c> is the new state. + </p> + <p> + <c><anno>Event</anno></c> is + an <c>{EventType,EventContent}</c> tuple. + </p> + </item> + <tag> + <c> + {enter,<anno>State</anno>} + </c> + </tag> + <item> + <p> + Is produced by <c>gen_statem</c> + when the first state <c><anno>State</anno></c> is entered. + </p> + </item> + <tag> + <c> + {terminate,<anno>Reason</anno>,<anno>State</anno>} + </c> + </tag> + <item> + <p> + Is produced by <c>gen_statem</c> + when it terminates with reason <c><anno>Reason</anno></c> + in state <c><anno>State</anno></c>. + </p> + </item> + </taglist> + </desc> </datatype> <datatype> <name name="dbg_opt"/> @@ -123,6 +271,9 @@ <name name="dbg_fun"/> </datatype> <datatype> + <name name="debug_option"/> + </datatype> + <datatype> <name name="format_fun"/> </datatype> </datatypes> @@ -532,6 +683,12 @@ <name name="get_debug" arity="3" since=""/> <fsummary>Get the data associated with a debug option.</fsummary> <desc> + <warning> + <p> + <c>get_debug/3</c> is deprecated since it returns + data of an internal type only useful for debugging. + </p> + </warning> <p>Gets the data associated with a debug option. <c><anno>Default</anno></c> is returned if <c><anno>Item</anno></c> is not found. Can be @@ -605,6 +762,18 @@ </func> <func> + <name name="get_log" arity="1" since="OTP-22.0"/> + <fsummary>Return the logged events in the debug structure.</fsummary> + <desc> + <p> + Returns the logged system events in the debug structure, + that is the last argument to + <seealso marker="#handle_debug/4"><c>handle_debug/4</c></seealso>. + </p> + </desc> + </func> + + <func> <name since="">Module:system_code_change(Misc, Module, OldVsn, Extra) -> {ok, NMisc}</name> <fsummary>Called when the process is to perform a code change.</fsummary> |