my %h2=(
'AAA' => 'aaa',
'BBB' => 'bbb',
'CCC' => {'A1' => a1,
          'B1' => 'b1',
          'C1' => {'A2' => a2,'B2' => 'b2','C2' => 'c2END'}},
'DDD' => 'ddd',
);


my $ref2 = \%h2;

&ddump($ref2);

sub ddump
{
  my $ref  = shift;
  my $deep = shift||1;
  foreach my $k (sort keys %{$ref})
          {
            if (ref( ${$ref}{$k}))  {print "\t" x $deep."$k =>\n"; 
             &ddump (${$ref}{$k}, ($deep+1))
            }
            else {print "\t" x ($deep)."$k => ${$ref}{$k}\n";}
            $deep-1;
          }
}