perl option to trace execution

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: perl option by Fletch (Bishop) on Jan 05, 2005 at 16:43 UTC
Try installing Devel::Trace and then use `perl -d:Trace foo`. That'll get you something similar to a shell's `set -x` functionality.	[reply] [d/l]
Re: perl option by jonadab (Parson) on Jan 05, 2005 at 22:25 UTC
I just want to pipe up briefly in support of Devel::Trace. It has a much lower learning curve than most of the other suggestions and does precisely what Anonymous Monk asked for.	[reply]
Re^2: perl option by DrHyde (Prior) on Jan 06, 2005 at 10:04 UTC
the `-d:Trace` can go on a shebang line too.	[reply] [d/l]
Re: perl option by qq (Hermit) on Jan 05, 2005 at 16:43 UTC
Try the perl debugger. Update: and `perldoc perldebug`, of course.	[reply] [d/l]
Re: perl option by Popcorn Dave (Abbot) on Jan 05, 2005 at 17:03 UTC
You may want to try the Graphical Debugger. It's written in Perl/Tk and has saved my bacon numerous times. You can watch your variables as your program executes - which is what I assume you wanted to do with the print statements you don't want to liberally sprinkle all across your program. The really nice thing is that you can also contract or expand arrays, hashes and complex data structures so you can see how they're being modified. Good luck! Useless trivia: In the 2004 Las Vegas phone book there are approximately 28 pages of ads for massage, but almost 200 for lawyers.	[reply]
Re: perl option by hubb0r (Pilgrim) on Jan 05, 2005 at 20:24 UTC
perl -d script.pl Takes a little learning to use the debugger. There's a graphical debugger addon that I've recently been using that's (in my opinion) very useful, and fairly stable. Its Devel::ptkdb and is invoked via perl -d:ptkdb script.pl. More info here: http://search.cpan.org/~aepage/Devel-ptkdb-1.1091/ptkdb.pm	[reply]
Re: perl option by techra (Pilgrim) on Jan 05, 2005 at 22:12 UTC
There's also a couple of other ways I've always found to be helpful in debugging perl scripts, especially since I mostly work in a web environment. Setting a scalar (say $debug) to 1 or 0 at function call and having your print functions conditional on $debug being true. ( print "I'm here" if $debug ). Better yet, writing your own debug function that listens to some higher-level variable is also a great way to do it. I also recommend the very nifty Smart::Comments from CPAN, which allows you to use specially formated # comments based on conditions, printed to the buffer.	[reply]
Re^2: perl option by RMGir (Prior) on Jan 06, 2005 at 13:13 UTC
I think you mean Smart::Comments (using the cpan:// syntax). There's no Smart::Comments node on perlmonks. BTW, thanks for the pointer, that's an interesting looking module! Mike	[reply]
Re: perl option by neilwatson (Priest) on Jan 05, 2005 at 19:44 UTC
Never underestimate the use of `print` and `die` statements. They are simple but valuable during development. Neil Watson watson-wilson.ca	[reply] [d/l] [select]
Re: perl option to trace execution by mkirank (Chaplain) on Jan 06, 2005 at 05:51 UTC
I have written a node on Enabling GUI Debugging under Mod_Perl, you can do a similar debgging using ptkdb	[reply]
Re: perl option to trace execution by DigitalKitty (Parson) on Jan 06, 2005 at 18:01 UTC
Hi Anonymous Monk. The Devshed has many interesting tutorials and I thought you might enjoy this one in particular: Using the Perl Debugger Thanks, ~Katie	[reply]
Re: perl option to trace execution by Anonymous Monk on May 12, 2016 at 01:44 UTC
Use the debugger's autotrace setting. "perl -d foo.pl", then at the debugger prompt, turn on auto trace "o AutoTrace=1". "c" to continue program execution and it will show each line as it is executed.	[reply]


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