aboutsummaryrefslogtreecommitdiffstats
path: root/lib/stdlib/doc/src/gen_server.xml
diff options
context:
space:
mode:
authorRaimo Niskanen <[email protected]>2017-09-06 12:06:02 +0200
committerGitHub <[email protected]>2017-09-06 12:06:02 +0200
commit28759f8cbde480be7782bac9169eeb9e4fb60bce (patch)
tree7c5898dd60e290621ebddcd717ba1b071bb44513 /lib/stdlib/doc/src/gen_server.xml
parent5785903d249026b7698ae48bb6e154f5e2a36c9b (diff)
parent69e009e3e1ad899a4609ff327a08512c86dba374 (diff)
downloadotp-28759f8cbde480be7782bac9169eeb9e4fb60bce.tar.gz
otp-28759f8cbde480be7782bac9169eeb9e4fb60bce.tar.bz2
otp-28759f8cbde480be7782bac9169eeb9e4fb60bce.zip
Merge pull request #1490 from josevalim/jv-gen-server-continue
Add {continue, Term} and handle_continue/2 to gen_server
Diffstat (limited to 'lib/stdlib/doc/src/gen_server.xml')
-rw-r--r--lib/stdlib/doc/src/gen_server.xml52
1 files changed, 51 insertions, 1 deletions
diff --git a/lib/stdlib/doc/src/gen_server.xml b/lib/stdlib/doc/src/gen_server.xml
index 7d137fc772..da74e793e6 100644
--- a/lib/stdlib/doc/src/gen_server.xml
+++ b/lib/stdlib/doc/src/gen_server.xml
@@ -60,6 +60,8 @@ gen_server:abcast -----> Module:handle_cast/2
- -----> Module:handle_info/2
+- -----> Module:handle_continue/2
+
- -----> Module:terminate/2
- -----> Module:code_change/3</pre>
@@ -88,6 +90,13 @@ gen_server:abcast -----> Module:handle_cast/2
implies at least two garbage collections (when hibernating and
shortly after waking up) and is not something you want to do
between each call to a busy server.</p>
+
+ <p>If the <c>gen_server</c> process needs to perform an action
+ immediately after initialization or to break the execution of a
+ callback into multiple steps, it can return <c>{continue,Continue}</c>
+ in place of the time-out or hibernation value, which will immediately
+ invoke the <c>handle_continue/2</c> callback.</p>
+
</description>
<funcs>
@@ -610,12 +619,15 @@ gen_server:abcast -----> Module:handle_cast/2
<v>State = term()</v>
<v>Result = {reply,Reply,NewState} | {reply,Reply,NewState,Timeout}</v>
<v>&nbsp;&nbsp;| {reply,Reply,NewState,hibernate}</v>
+ <v>&nbsp;&nbsp;| {reply,Reply,NewState,{continue,Continue}}</v>
<v>&nbsp;&nbsp;| {noreply,NewState} | {noreply,NewState,Timeout}</v>
<v>&nbsp;&nbsp;| {noreply,NewState,hibernate}</v>
+ <v>&nbsp;&nbsp;| {noreply,NewState,{continue,Continue}}</v>
<v>&nbsp;&nbsp;| {stop,Reason,Reply,NewState} | {stop,Reason,NewState}</v>
<v>&nbsp;Reply = term()</v>
<v>&nbsp;NewState = term()</v>
<v>&nbsp;Timeout = int()>=0 | infinity</v>
+ <v>&nbsp;Continue = term()</v>
<v>&nbsp;Reason = term()</v>
</type>
<desc>
@@ -673,9 +685,11 @@ gen_server:abcast -----> Module:handle_cast/2
<v>State = term()</v>
<v>Result = {noreply,NewState} | {noreply,NewState,Timeout}</v>
<v>&nbsp;&nbsp;| {noreply,NewState,hibernate}</v>
+ <v>&nbsp;&nbsp;| {noreply,NewState,{continue,Continue}}</v>
<v>&nbsp;&nbsp;| {stop,Reason,NewState}</v>
<v>&nbsp;NewState = term()</v>
<v>&nbsp;Timeout = int()>=0 | infinity</v>
+ <v>&nbsp;Continue = term()</v>
<v>&nbsp;Reason = term()</v>
</type>
<desc>
@@ -690,6 +704,41 @@ gen_server:abcast -----> Module:handle_cast/2
</func>
<func>
+ <name>Module:handle_continue(Continue, State) -> Result</name>
+ <fsummary>Handle a continue instruction.</fsummary>
+ <type>
+ <v>Continue = term()</v>
+ <v>State = term()</v>
+ <v>Result = {noreply,NewState} | {noreply,NewState,Timeout}</v>
+ <v>&nbsp;&nbsp;| {noreply,NewState,hibernate}</v>
+ <v>&nbsp;&nbsp;| {noreply,NewState,{continue,Continue}}</v>
+ <v>&nbsp;&nbsp;| {stop,Reason,NewState}</v>
+ <v>&nbsp;NewState = term()</v>
+ <v>&nbsp;Timeout = int()>=0 | infinity</v>
+ <v>&nbsp;Continue = term()</v>
+ <v>&nbsp;Reason = normal | term()</v>
+ </type>
+ <desc>
+ <note>
+ <p>This callback is optional, so callback modules need to
+ export it only if they return <c>{continue,Continue}</c>
+ from another callback. If continue is used and the callback
+ is not implemented, the process will exit with <c>undef</c>
+ error.</p>
+ </note>
+ <p>This function is called by a <c>gen_server</c> process whenever
+ a previous callback returns <c>{continue, Continue}</c>.
+ <c>handle_continue/2</c> is invoked immediately after the previous
+ callback, which makes it useful for performing work after
+ initialization or for splitting the work in a callback in
+ multiple steps, updating the process state along the way.</p>
+ <p>For a description of the other arguments and possible return values,
+ see <seealso marker="#Module:handle_call/3">
+ <c>Module:handle_call/3</c></seealso>.</p>
+ </desc>
+ </func>
+
+ <func>
<name>Module:handle_info(Info, State) -> Result</name>
<fsummary>Handle an incoming message.</fsummary>
<type>
@@ -697,6 +746,7 @@ gen_server:abcast -----> Module:handle_cast/2
<v>State = term()</v>
<v>Result = {noreply,NewState} | {noreply,NewState,Timeout}</v>
<v>&nbsp;&nbsp;| {noreply,NewState,hibernate}</v>
+ <v>&nbsp;&nbsp;| {noreply,NewState,{continue,Continue}}</v>
<v>&nbsp;&nbsp;| {stop,Reason,NewState}</v>
<v>&nbsp;NewState = term()</v>
<v>&nbsp;Timeout = int()>=0 | infinity</v>
@@ -726,7 +776,7 @@ gen_server:abcast -----> Module:handle_cast/2
<type>
<v>Args = term()</v>
<v>Result = {ok,State} | {ok,State,Timeout} | {ok,State,hibernate}</v>
- <v>&nbsp;| {stop,Reason} | ignore</v>
+ <v>&nbsp;| {ok,State,{continue,Continue}} | {stop,Reason} | ignore</v>
<v>&nbsp;State = term()</v>
<v>&nbsp;Timeout = int()>=0 | infinity</v>
<v>&nbsp;Reason = term()</v>