You're missing a $. Your code should look like this: 
    print keys %{ $hash_ref -> { key } };

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The symbolic reference error comes from your code trying to dereference a string: 
    hash_ref->{key}

[download]
hash_ref isn't a hash ref, it's a string. $hash_ref is the hash ref.

In reply to Re: Why is this a symbolic reference? by btrott
in thread Why is this a symbolic reference? by Anonymous Monk

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