allowing Data::Dumper within safe.pm

gideondsouza has asked for the wisdom of the Perl Monks concerning the following question:

So I use Safe.pm, to allow and deny certain operations. When I use Data::Dumper I get:

Unsafe code detected: 
'eval "string"' trapped by operation mask at /usr/.../Carp.pm line 160
+.
Compilation failed in require at /usr/../Data/Dumper.pm line 22.
BEGIN failed--compilation aborted at /usr/../Data/Dumper.pm line 22.
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This is what my Safe permit/denies look like:

$compartment->deny(qw(:base_io :ownprocess :subprocess :filesys_read :
+sys_db :filesys_open :filesys_write :dangerous));
$compartment->permit(qw(print say pack unpack require caller));
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Question: What should I allow to make Data::Dumper work? I tried permit("eval") but it says no operator recognized

Note, this is NOT production code, this is a learning project I'm working on.

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Re: allowing Data::Dumper within safe.pm by Anonymous Monk on Feb 12, 2013 at 09:17 UTC
Question: What should I allow to make Data::Dumper work? I tried permit("eval") but it says no operator recognized Mwaaah? Following http://search.cpan.org/dist/Safe/Safe.pm#permit_%28OP,_...%29 says to see http://search.cpan.org/~dom/perl-5.12.5/ext/Opcode/Opcode.pm#Predefined_Opcode_Tags, search for eval, i see entereval and leaveeval -- so try something from that list :) I assume you can always http://search.cpan.org/dist/Safe/Safe.pm#share_from_%28PACKAGE,_ARRAYREF%29 Dumper	[reply]
Re^2: allowing Data::Dumper within safe.pm by gideondsouza (Pilgrim) on Feb 12, 2013 at 09:34 UTC
Ah! I've tried entereval and leaveeval and it still gives me the exact same message! :( How should I use share_from, I don't quite understand what it does!	[reply]
Re^3: allowing Data::Dumper within safe.pm by Anonymous Monk on Feb 12, 2013 at 09:44 UTC
How should I use share_from, I don't quite understand what it does! Me neither :) You can take a look at Safe::Hole and ?node_id=3989;HIT=safe;re=N... good luck, this be a dusty attic	[reply]
Re^4: allowing Data::Dumper within safe.pm by MidLifeXis (Monsignor) on Feb 12, 2013 at 13:17 UTC
Re^3: allowing Data::Dumper within safe.pm by 7stud (Deacon) on Feb 12, 2013 at 17:24 UTC
share() allows you to specify which global variables in your program that you want your compartment to be able to see. However, you can only specify simple names, like '$x', i.e. names from the current namespace. share_from() allows you to specify more complex variable names, i.e. variables from a different namespace, e.g. package X::Y::Z. However, I've not succeeded in getting either to work. If you do, please post an example.	[reply]

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