diff options
Diffstat (limited to 'system/doc')
| -rw-r--r-- | system/doc/design_principles/spec_proc.xml | 16 | ||||
| -rw-r--r-- | system/doc/reference_manual/modules.xml | 19 |
2 files changed, 24 insertions, 11 deletions
diff --git a/system/doc/design_principles/spec_proc.xml b/system/doc/design_principles/spec_proc.xml index 69bf2e0448..e4fb5fdca7 100644 --- a/system/doc/design_principles/spec_proc.xml +++ b/system/doc/design_principles/spec_proc.xml @@ -4,7 +4,7 @@ <chapter> <header> <copyright> - <year>1997</year><year>2013</year> + <year>1997</year><year>2014</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -431,11 +431,11 @@ loop(...) -> <section> <title>User-Defined Behaviours</title> - <p>To implement a user-defined behaviour, write code similar to + <p><marker id="behaviours"/>To implement a user-defined behaviour, write code similar to code for a special process but calling functions in a callback module for handling specific tasks.</p> <p>If it is desired that the compiler should warn for missing callback - functions, as it does for the OTP behaviours, add callback attributes in the + functions, as it does for the OTP behaviours, add <c>-callback</c> attributes in the behaviour module to describe the expected callbacks:</p> <code type="none"> -callback Name1(Arg1_1, Arg1_2, ..., Arg1_N1) -> Res1. @@ -445,15 +445,15 @@ loop(...) -> <p>where <c>NameX</c> are the names of the expected callbacks and <c>ArgX_Y</c>, <c>ResX</c> are types as they are described in Specifications for functions in <seealso marker="../reference_manual/typespec">Types and - Function Specifications</seealso>. The whole syntax of spec attributes is - supported by callback attributes.</p> + Function Specifications</seealso>. The whole syntax of <c>-spec</c> attribute is + supported by <c>-callback</c> attribute.</p> <p>Alternatively you may directly implement and export the function:</p> <code type="none"> behaviour_info(callbacks) -> - [{Name1,Arity1},...,{NameN,ArityN}].</code> - <p>where each <c>{Name,Arity}</c> specifies the name and arity of a callback + [{Name1, Arity1},...,{NameN, ArityN}].</code> + <p>where each <c>{Name, Arity}</c> specifies the name and arity of a callback function. This function is otherwise automatically generated by the compiler - using the callback attributes.</p> + using the <c>-callback</c> attributes.</p> <p>When the compiler encounters the module attribute <c>-behaviour(Behaviour).</c> in a module <c>Mod</c>, it will call <c>Behaviour:behaviour_info(callbacks)</c> and compare the result with the diff --git a/system/doc/reference_manual/modules.xml b/system/doc/reference_manual/modules.xml index 9e5f4de385..cd4c3a1b1b 100644 --- a/system/doc/reference_manual/modules.xml +++ b/system/doc/reference_manual/modules.xml @@ -4,7 +4,7 @@ <chapter> <header> <copyright> - <year>2003</year><year>2013</year> + <year>2003</year><year>2014</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -134,8 +134,21 @@ fact(0) -> % | standard behaviours <c>gen_server</c>, <c>gen_fsm</c>, <c>gen_event</c> or <c>supervisor</c>.</p> <p>The spelling <c>behavior</c> is also accepted.</p> - <p>Read more about behaviours and callback modules in OTP Design - Principles.</p> + <p>The callback functions of the module can be specified either + directly by the exported function <c>behaviour_info/1</c>:</p> + <pre> +behaviour_info(callbacks) -> Callbacks.</pre> + <p>or by a <c>-callback</c> attribute for each callback + function:</p> + <pre> +-callback Name(Arguments) -> Result.</pre> + <p>where <c>Arguments</c> is a list of zero or more arguments. + The <c>-callback</c> attribute is to be preferred since the + extra type information can be used by tools to produce + documentation or find discrepancies.</p> + <p>Read more about behaviours and callback modules in + <seealso marker="doc/design_principles:spec_proc#behaviours"> + OTP Design Principles</seealso>.</p> </section> <section> |