Log::Log4perl::Resurrector(3) Dark Magic to resurrect hidden L4p statements


Loading "use Log::Log4perl::Resurrector" causes subsequently loaded modules to have their hidden

    ###l4p use Log::Log4perl qw(:easy);
    ###l4p DEBUG(...)
    ###l4p INFO(...)

statements uncommented and therefore 'resurrected', i.e. activated.

This allows for a module "Foobar.pm" to be written with Log4perl statements commented out and running at full speed in normal mode. When loaded via

    use Foobar;

all hidden Log4perl statements will be ignored.

However, if a script loads the module "Foobar" after loading "Log::Log4perl::Resurrector", as in

    use Log::Log4perl::Resurrector;
    use Foobar;

then "Log::Log4perl::Resurrector" will have put a source filter in place that will extract all hidden Log4perl statements in "Foobar" before "Foobar" actually gets loaded.

Therefore, "Foobar" will then behave as if the

    ###l4p use Log::Log4perl qw(:easy);
    ###l4p DEBUG(...)
    ###l4p INFO(...)

statements were actually written like

    use Log::Log4perl qw(:easy);

and the module "Foobar" will indeed be Log4perl-enabled. Whether any activated Log4perl statement will actually trigger log messages, is up to the Log4perl configuration, of course.

There's a startup cost to using "Log::Log4perl::Resurrector" (all subsequently loaded modules are examined) but once the compilation phase has finished, the perl program will run at full speed.

Some of the techniques used in this module have been stolen from the "Acme::Incorporated" CPAN module, written by chromatic. Long live CPAN!


Copyright 2002-2013 by Mike Schilli <[email protected]> and Kevin Goess <[email protected]>.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.


Please contribute patches to the project on Github:


Send bug reports or requests for enhancements to the authors via our

MAILING LIST (questions, bug reports, suggestions/patches): [email protected]

Authors (please contact them via the list above, not directly): Mike Schilli <[email protected]>, Kevin Goess <[email protected]>

Contributors (in alphabetical order): Ateeq Altaf, Cory Bennett, Jens Berthold, Jeremy Bopp, Hutton Davidson, Chris R. Donnelly, Matisse Enzer, Hugh Esco, Anthony Foiani, James FitzGibbon, Carl Franks, Dennis Gregorovic, Andy Grundman, Paul Harrington, Alexander Hartmaier David Hull, Robert Jacobson, Jason Kohles, Jeff Macdonald, Markus Peter, Brett Rann, Peter Rabbitson, Erik Selberg, Aaron Straup Cope, Lars Thegler, David Viner, Mac Yang.