add comment clarifying the need to pattern match in `with_exit_handler/2'

1 files changed, 3 insertions, 0 deletions

diff --git a/src/rabbit_misc.erl b/src/rabbit_misc.erl
index 49b467166b..6ce1d06848 100644
--- a/src/rabbit_misc.erl
+++ b/src/rabbit_misc.erl
@@ -421,6 +421,9 @@ throw_on_error(E, Thunk) ->
         Res             -> Res
     end.
 
+%% Note the code duplication between this and `with_exit_handler/2' below - we
+%% can't use arbitrary functions in guards, and we can't re-throw runtime
+%% errors.
 is_benign_exit({R, _}) when R =:= noproc; R =:= nodedown; R =:= normal;
                             R =:= shutdown ->
     true;