Devel::Events::Filter::Warn - log every event to STDERR


        # can be used as a handler
        my $h = Devel::Events::Filter::Warn->new();

        # or as a filter in a handler chain

        my $f = Devel::Events::Filter::Warn->new(
                handler => $sub_handler,


This is a very simple debugging aid to see that your filter/handler chains are set up correctly.

A useful helper function you can define is something along the lines of:

        sub _warn_events ($) {
                my $handler = shift;
                Devel::Events::Filter::Warn->new( handler => $handler );

and then prefix handlers which seem to not be getting their events with _warn_events in the source code.


filter_event @event

calls warn "@event". and returns the event unfiltered.