Devel::Trepan — A gdb-like Perl debugger

A modular, testable gdb-like debugger in the family of the "Trepanning" debuggers (trepan3k, trepan-ni, bashdb, zshdb). The command set is modeled off of gdb, but other command sets are possible.

Features:

• precise location via decomplation (via plugin Trepan::Devel::Deparse
• has extensive online-help,
• syntax highlighting of Perl code
• context-sensitive command completion
• out-of-process and remote debugging
• interactive shell support
• code disassembly
• gdb syntax
• easy extensibility at several levels
  • command aliases
  • a user-supplied command directory
  • Perl Plugin module such as Trepan::Devel::Disassemble
• is more modular
• comes with extensive tests
• is not as ugly as perl5db

Synopsis

From a shell:

$ trepan.pl [trepan-opts] [--] perl-program [perl-program-opts]

Or for those who prefer the traditional Perlish way:

$ perl -d:Trepan perl-program [perl-program-opts]

The problem with the above "perlish" approach is that there are a number of default options won't get set intelligently. If that matters, you'll have to set them either with a debugger command or via environment variable TREPANPL_OPTS. To see the environement variables, run trepan.pl with the --verbose option.

Calling the debugger from inside your Perl program using Joshua ben Jore's Enbugger:

# This needs to be done once and could even be in some sort of
# conditional code
require Enbugger; Enbugger->load_debugger( 'trepan' );

# Alternatively, to unconditionally load Enbugger and trepan:
use Enbugger 'trepan';

# work, work, work...
# Oops! there was an error! Enable the debugger now!
Enbugger->stop;  # or Enbugger->stop if ...

Or if you just want POSIX-shell-like set -x line tracing:

$ trepan.pl -x -- perl-program [perl-program-opts]

Inside the debugger tracing is turned on using the command set trace print. There is extensive help from the help command.

Installation

To install this Devel::Trepan from source code:

$ cpan Module::Build
$ perl Build.PL
$ ./Build installdeps
$ make
$ make test
$ make install # May need sudo

or to install from CPAN:

$ cpanm Devel::Trepan

See Also

• On writing a new Perl Debugger (Part 1 - Why?)
• Devel::Trepan Debugger command aliases and command completion
• Devel::Trepan Debugger evaluation of Perl statements
• Location, Location, Location
• Exact Perl location with B::DeparseTree (and Devel::Callsite)
• wiki

Licence and Copyright

Copyright (C) 2011-2015, 2019 Rocky Bernstein rocky@cpan.org

This program is distributed WITHOUT ANY WARRANTY, including but not limited to the implied warranties of merchantability or fitness for a particular purpose.

The program is free software. You may distribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation (either version 2 or any later version) and the Perl Artistic License as published by O’Reilly Media, Inc. Please open the files named gpl-2.0.txt and Artistic for a copy of these licenses.