for people (like me) who had to look it up: here's a link to "Not Exactly a Hash Tutorial"

Basically, Data::Dumper takes a perl datastructure and turns it into a string containing perl code that, when eval()ed (that is, run as code), returns an equivalent data structure. This is useful for many reasons, but a very simple use is to print out a data-structure to see if it matches what you think it is.

Example:

use Data::Dumper qw(Dumper); # impor the Dumper() subroutine
my %hash = ( a => 1, b => 2, c => 3 );
print Dumper(\%hash);  # note the \ backslash; Dumper() takes referenc
+es as arguments
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Output:

$VAR1 = {
          'c' => 3,
          'a' => 1,
          'b' => 2
        };
[download]