Hash entries (values) can be anything, including objects.
Hash keys can only be strings.

If you need objects for keys, have a look at Tie::RefHash.

Update: Here's an example of storing an object: 

{
   package MyClass;
   sub new { bless {}, shift }
   sub doit { print("Method called\n"); }
}

my $o = MyClass->new();
my %hash = ( object => $o );
$hash{object}->doit();  # Prints "Method called"

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In reply to Re: HASH keys preserve class ? by ikegami
in thread HASH keys preserve class ? by Anonymous Monk

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