Question

In a Perl project,usually how to fix bugs in the script?
Please can anyone give some idea.
Thanks in advance.

Answer 1

My first think is perldoc perldebug

I think it’s the better place to start.

My second is : always put

use strict;
use warnings;

on the top of your script, and you can put

use diagnostics;

too, for producing a more verbose warning diagnostics

---

Before opening the Pandora box, takes advantage of the Perl module Data::Dumper.

It’s useful to display all (nested) data structures and objects, see (I use perlconsole, it’s nice to try some tricks):

$ perlconsole
Perl Console 0.4
Perl> my $ref = { foo => 'bar', arr => [ 1, 2, 3, [ qw/a z e r t y/ ] ] }
HASH(0x1fc25a8)

Perl> use Data::Dumper;
Perl> print Dumper  $ref;
$VAR1 = {
          'foo' => 'bar',
          'arr' => [
                     1,
                     2,
                     3,
                     [
                       'a',
                       'z',
                       'e',
                       'r',
                       't',
                       'y'
                     ]
                   ]
        };
1

Perl> 

---

You will see that Perl can run a script in a debugger with

perl -d -e 42 script.pl

help said :

$ perl --help | grep -- '-d'
  -d[:debugger]     run program under debugger

You can “trace” it too with :

perl -d:Trace script.pl

---

There’s a gui debugger too, it comes with Devel::ptkdb module, example :

perl -d:ptkdb script.pl

---

Try

perlcritic

too, a Command-line interface to critique Perl source.

---

Profiling your code is also possible, see

http://metacpan.org/pod/Devel::NYTProf

http://blog.timbunce.org/2008/07/15/nytprof-v2-a-major-advance-in-perl-profilers/