diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/stdlib/doc/src/gen_statem.xml | 5 | ||||
| -rw-r--r-- | lib/stdlib/src/gen_statem.erl | 28 |
2 files changed, 22 insertions, 11 deletions
diff --git a/lib/stdlib/doc/src/gen_statem.xml b/lib/stdlib/doc/src/gen_statem.xml index d19602b67c..5eb13db1aa 100644 --- a/lib/stdlib/doc/src/gen_statem.xml +++ b/lib/stdlib/doc/src/gen_statem.xml @@ -1973,6 +1973,11 @@ handle_event(_, _, State, Data) -> <v>Ignored = term()</v> </type> <desc> + <note> + <p>This callback is optional, so callback modules need not + export it. The <c>gen_statem</c> module provides a default + implementation without cleanup.</p> + </note> <p> This function is called by a <c>gen_statem</c> when it is about to terminate. It is to be the opposite of diff --git a/lib/stdlib/src/gen_statem.erl b/lib/stdlib/src/gen_statem.erl index d7e8504564..ae50651c06 100644 --- a/lib/stdlib/src/gen_statem.erl +++ b/lib/stdlib/src/gen_statem.erl @@ -289,6 +289,7 @@ -optional_callbacks( [init/1, % One may use enter_loop/5,6,7 instead format_status/2, % Has got a default implementation + terminate/3, % Has got a default implementation %% state_name/3, % Example for callback_mode() =:= state_functions: %% there has to be a StateName/3 callback function @@ -1560,17 +1561,22 @@ terminate( Class, Reason, Stacktrace, Debug, #{module := Module, state := State, data := Data, postponed := P} = S, Q) -> - try Module:terminate(Reason, State, Data) of - _ -> ok - catch - _ -> ok; - C:R -> - ST = erlang:get_stacktrace(), - error_info( - C, R, ST, S, Q, P, - format_status(terminate, get(), S)), - sys:print_log(Debug), - erlang:raise(C, R, ST) + case erlang:function_exported(Module, terminate, 3) of + true -> + try Module:terminate(Reason, State, Data) of + _ -> ok + catch + _ -> ok; + C:R -> + ST = erlang:get_stacktrace(), + error_info( + C, R, ST, S, Q, P, + format_status(terminate, get(), S)), + sys:print_log(Debug), + erlang:raise(C, R, ST) + end; + false -> + ok end, _ = case Reason of |