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What Data::Dumper usually does is dump your data in a nice, legible format. There are actually quite a few uses for the module, but most programmers start using it with something like the following:

#!/usr/bin/perl -w use strict; use Data::Dumper; my $foo = 'test'; my @array = qw/ this is an array /; my %hash = ( one => 'une', two => 'deux', three => \&some_subroutine, four => { uh => 'oh', name => [qw/Publius Ovidius Naso/] } ); my $bar; print Dumper $foo, \@array; print Dumper \%hash; print Dumper $bar;

Thus, you can use Data::Dumper to quickly 'dump' the contents of your variables. Yes, you can print a scalar, but printing out complex data structures (like the hash, above) can be tedious. Data::Dumper frees you from the hard work and makes debugging a breeze. If you do CGI work, try dumping the CGI object sometime. It's most informative :)

Once you get used to using Data::Dumper, reread the documentation. It will be easier to understand.

Cheers,
Ovid

Update: For the record, this is the output of the above code:

$VAR1 = 'test'; $VAR2 = [ 'this', 'is', 'an', 'array' ]; $VAR1 = { 'one' => 'une', 'three' => sub { "DUMMY" }, 'two' => 'deux', 'four' => { 'uh' => 'oh', 'name' => [ 'Publius', 'Ovidius', 'Naso' ] } }; $VAR1 = undef;

I don't see how munchie could have gotten the output listed below.

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In reply to (Ovid) Re: Data::Dumper in a nutshell? by Ovid
in thread Data::Dumper in a nutshell? by munchie

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