in reply to Address of anonymous hash

You should never use a memory-address as a “key.”   It is never wise to build code that is in any way dependent upon “an implementation side-effect,” even if that side-effect appears to be stable.   You will get burned ...

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Re^2: Address of anonymous hash
by ikegami (Patriarch) on Feb 02, 2011 at 17:28 UTC

    You should never use a memory-address as a “key.”

    Have you heard of inside-out objects? At the base, they do exactly what just proclaimed shouldn't be done. 

    {
   my %objs;

   sub new {
      my $obj = { ... };
      my $key = 0+$obj;
      $data{$key} = $rec;
      return $key;
   }
}

    [download]

    (Blessing omitted for clarity.)

    I don't know to what side-effect you are referring. That numification of a reference returns its address? That's safe.

[reply]
[d/l]
Re^2: Address of anonymous hash
by ikegami (Patriarch) on Feb 02, 2011 at 17:29 UTC

    You should never use a memory-address as a “key.”

    Have you heard of inside-out objects? At the base, they do exactly what just proclaimed shouldn't be done. 

    {
   my %objs;

   sub new {
      my $obj = { ... };
      my $key = 0+$obj;
      $data{$key} = $rec;
      return $key;
   }
}

    [download]

    (Blessing omitted for clarity.)

    I don't know to what side-effect you are referring. That numification of a reference returns its address? That's safe.

[reply]
[d/l]
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