Log::Any::IfLOG - Load Log::Any only if "logging is enabled"


This document describes version 0.090 of Log::Any::IfLOG (from Perl distribution Log-Any-IfLOG), released on 2019-01-09.


 use Log::Any::IfLOG '$log';


This module is a drop-in replacement/wrapper for Log::Any to be used from your modules. This is a quick-hack solution to avoid the cost of loading Log::Any under "normal condition". Since Log::Any 1.00, startup overhead increases to about 7-10ms on my PC/laptop (from under 1ms for the previous version). Because I want to keep startup overhead of CLI apps under 50ms (see Perinci::CmdLine::Lite) to keep tab completion from getting a noticeable lag, every millisecond counts.

This module will only load Log::Any when "logging is enabled". Otherwise, it will just return without loading anything. If $log is requested in import, a fake object is returned that responds to methods like debug, is_debug and so on but will do nothing when called and just return 0.

To determine "logging is enabled":

  • Is $ENABLE_LOG defined?

    This package variable can be used to force "logging enabled" (if true) or "logging disabled" (if false). Normally, you don't need to do this except for testing.

  • Is Log::Any is already loaded (from %INC)?

    If Log::Any is already loaded, it means we have taken the overhead hit anyway so logging is enabled.

  • Is one of log-related environment variables true?

    If one of LOG, TRACE, or DEBUG, or VERBOSE, or QUIET, or LOG_LEVEL is true then logging is enabled. These variables are used by Perinci::CmdLine.

    Otherwise, logging is disabled.


$ENABLE_LOG => bool

This setting can be forced to force loading Log::Any or not.


LOG => bool

TRACE => bool

DEBUG => bool

VERBOSE => bool

QUIET => bool

LOG_LEVEL => str


Please visit the project's homepage at


Source repository is at


Please report any bugs or feature requests on the bugtracker website

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.




perlancar <>


This software is copyright (c) 2019, 2015 by

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