Thanx toolic, indeed I have to read this thoroughly.

I was actually looking for a way to display the difference between deep and flat copy to a newbie, and no figured out that the Seen-Mechanism in Data::Dumper already reveals it, without the need to print the Ref-IDs. 8)

  DB<90> $hr2={%$hr1}  # shallow copy
 
  DB<91>  print Data::Dumper->Dump([$hr1,$hr2],[qw/hr1 hr2/])
$hr1 = {
         'a' => {
                  'b' => {
                           'c' => 1
                         }
                }
       };
$hr2 = {
         'a' => $hr1->{'a'}
       };
 
  DB<92> x $hr1,$hr2
0  HASH(0x8b64b78)
   'a' => HASH(0x8b64c18)
      'b' => HASH(0x8af9120)
         'c' => 1
1  HASH(0x8b156c0)
   'a' => HASH(0x8b64c18)
      -> REUSED_ADDRESS

[download]

Anyway IMHO an option to add the IDs as comments would be welcomed by many people as a valuable feature!

(update: maybe this can be done with Data::Dump::Streamer?)

Cheers Rolf

UDPATE: improved code example

In reply to Re^2: Making Data::Dumper also displaying (stringified) Ref-ID's? by LanX
in thread Making Data::Dumper also displaying (stringified) Ref-ID's? by LanX

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