That's a perfect reason to pick up Randal's new book: Learning Perl Objects, References & Modules. There is also perldoc perlref and perldoc perlreftut. If you are ever in doubt of what your memory structure looks like, use Data::Dumper to print it out! Here is a quick example of dereferencing an array of hashes.

#!/usr/bin/perl -w
 
use strict;
#  Data::Dumper so we can dump out datastructure later
use Data::Dumper;

#  Let's create an anonymous array with two elements, each a reference
+ to an anonymous hash.
my $aref=[
{a => '1', b => '2'},
{c => '3', d => '4'}
];

#Now dump each element of the array
print Dumper($aref->[0]);
print Dumper($aref->[1]);

#Now dereference single elements, the arrow '->' tells perl to derefen
+ce $aref, the you can select elements from the hash using the normal 
+{} syntax 
print "c is $aref->[1]{c}\n";
print "a is $aref->[0]{a}\n";

## Ouput
###############
$VAR1 = {
          'a' => '1',
          'b' => '2'
        };
$VAR1 = {
          'c' => '3',
          'd' => '4'
        };
c is 3
a is 1
[download]

HTH

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