That's not how to dereference a hash ref. You're trying to deref it as a scalar, which it isn't, and that's why it's throwing the error.

I was wrong... $$href{try} does actually work. My bad :) I can't figure out why you're receiving that error with the code you've supplied though. Can you post more context?

Dereference individual items with the -> deref operator:

# hashref
$h_ref->{try};

# arrayref
$aref->[0];

# scalar
$$scalar_ref;
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...and to dereference entire structures:

# hash
my %hash = %$hash_ref;

# array
my @array = @$aref;
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If you need to dereference an entire list-type reference out of a nested structure, you need to use the circumfix operator:

# hash
my %hash = %{ $hash_ref->{inner_href} };

# array
my @array = @{ $aref->[0] };
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A bit more complicated... extract one list-type variable out of a different list-type variable:

# array from href
my @array = @{ $href->{inner_array} };

# hash from array ref
my %hash = %{ $array->[0] };
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