How can I get a call stack listing in Perl?

Question

Is there a way I can access (for printout) a list of sub + module to arbitrary depth of sub-calls preceding a current position in a Perl script?

I need to make chan

Answer 1

You can use Devel::StackTrace.

use Devel::StackTrace;
my $trace = Devel::StackTrace->new;
print $trace->as_string; # like carp

It behaves like Carp's trace, but you can get more control over the frames.

The one problem is that references are stringified and if a referenced value changes, you won't see it. However, you could whip up some stuff with PadWalker to print out the full data (it would be huge, though).

Answer 2

This code works without any additional modules. Just include it where needed.

my $i = 1;
print STDERR "Stack Trace:\n";
while ( (my @call_details = (caller($i++))) ){
    print STDERR $call_details[1].":".$call_details[2]." in function ".$call_details[3]."\n";
}

Answer 3

caller can do that, though you may want even more information than that.

Answer 4

There's also Carp::confess and Carp::cluck.

Answer 5

Moving my comment to an answer:

1. Install Devel::Confess the right way

   cpanm Devel::Confess
   

2. Run with

   perl -d:Confess myscript.pl
   

On errors, this will show the whole call stack list.

Answer 6

One that is more pretty: Devel::PrettyTrace

use Devel::PrettyTrace;
bt;