Author image Kent Fredric (PAUSE Custodial Account)
and 1 contributors


Package::Debug - Add ENV/Config controlled debug tokens to your code


version 0.2.2


There is a lot of code on CPAN that has something like this in it:


or something like

    sub DEBUG {
        return if not $ENV{MY_PACKAGE_NAME_DEBUG};
        <real debug code>

or something like:

        *DEBUG=sub{ withdebug }
    } else {
        *DEBUG=sub { noop }

These are mostly simple and straight forward, ... however, they artificially limit what you can do, at the cost of making ugly code.

This module aims to implement the common utility, with less fuss:

    $ENV{MY_BAZ_DEBUG} = 1;

    package My::Baz;

    use Package::Debug;


    sub foo {

And all the right things should still occur.

Additionally, this module will eventually add a bunch of features, that are by default off, but can be toggled on using environment or configuration files.


  • Deferrable debug mechanism

    The defacto DEBUG() stub when not in a debug environment should be a no-op, or as close to a no-op as possible.

    However, when debugging is turned on, debugging back ends should also be controllable via env/configuaration, and proxy to things like Log::Message and friends.

  • Per-package debug granularity

    Every package will get its own independent DEBUG key, and DEBUG for a class can be toggled with an %ENV key relevant to that class.

  • Global Debugging

    In addition to package level granularity, global debugging can also be enabled, while still seeing the individual packages the debug message emanates from.


Kent Fredric <>


This software is copyright (c) 2013 by Kent Fredric <>.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.