Assuming (like me) you generally prefer logging to crack-pipe debugging sessions, have you considered more mainstream alternatives to your home-grown debug subroutine ... such as Log::Log4perl or Smart::Comments?

See also:

• Possible scoping issue with Log::Log4perl logger
• Log4Shell and Log::Log4perl
• In Defense of Smart::Comments
• Smart::Comments source filter on or off .. post compile?
• on Debuggers (see also: later version with more responses)

Building Perl References

• Re: Replicate Perl setup (Building and Installing Perl References) - if you're doing anything serious with Perl you DO NOT want to use the OS system perl as that way lies much pain, much better to build your own perl

Troubleshooting References

• Troubleshooting (wikipedia)
• Critical thinking (wikipedia)
• Process of elimination (wikipedia)

Logging References

Linux man pages:

• logger(1) - enter messages into the system log

perldoc:

• Sys::Syslog

CPAN:

• Log::Any by Doug Bell - Bringing loggers and listeners together
• Log::Any::Adapter::Syslog - Send Log::Any logs to syslog
• Log::Log4perl by Ed J - Log4j implementation for Perl
• Log::Dispatch by Dave Rolsky - Dispatches messages to one or more outputs

• Smart::Comments
• Devel::Trace

Perl Monks:

• Log::Log4Perl best practices by water
• help with Log::Log4perl config file by water

• Wanted: Opinions on Logging Frameworks
• Which logging module to use?
• Dependency to Log::Log4perl
• perl modules design for logging

• Re^2: Error Reporting from Module
• Logging and tracing with DBIx::Simple
• Re: Error Reporting from Module
• What modules should be added to the corelist?

• Re^3: RFC: 101 Perl PDL Exercises for Data Analysis by etj (2022) - suggests either perldl or pdl2 as a REPL, over the Perl debugger, especially for PDL stuff

• os upgrade breaks cgi by schwende (2024) - perl novice needs to debug a CGI Perl script that broke after an RHEL OS upgrade
• Re: catch die from say by stevieb (2024) - example using SMS::Send::Twilio to send a text message to his phone if an error occurs
• Seeing NULLs in my Log::Log4perl log file by talexb (2024) - seeing a blob of NULLs in the log file for a script that's using Log::Log4perl
• Write to rsyslog by slandry (2024) - write very simple print statements to Rsyslog (converting bash script to Perl)

• Logging with Log4perl (perlmaven)

• WWW::Mechanize::Chrome : random complaining that Log4perl is not initialised and test fails by bliako (2025) - doesn't like Log::Log4perl very much
• Re^2: WWW::Mechanize::Chrome : random complaining that Log4perl is not initialised and test fails by hippo (2025) - suggests trying Log::Any instead

Debugging References

• Category:Debugging (wikipedia)
• Debugging (wikipedia)
• Minimal reproducible example (wikipedia)
• Short, Self-Contained, Correct Example by haukex
• "It's not working" is not helpful

PM Nodes:

• on Debuggers References

• Basic debugging checklist by toolic (2009) - classic post
• Unbelievably Obvious Debugging Tip by dreadpiratepeter (2004) - debugging whitespace, cat command line options can help
• Debugging tips for segmentation faults? by Tanktalus (2005) - replies mention building perl with debugging symbols
• A Perl 3 bug in the debugger by pemungkah (2023) - we've had this bug in the Perl debugger for 32 years!

Added Later:

• I never use the debugger. by friedo (2005) - lots of responses (one from brian_d_foy)

Perl core docs:

• perldebug
• perldebtut

Other:

• Valgrind

See Also

• Re: Perl Memory problem ... (Memory Tools References)
• Re: eval to replace die? (Exceptions and Error Handling References)
• Re: Replicate Perl setup (Building and Installing Perl References)
• Effective Automated Testing

Many references were added later, long after the initial reply was made.