I've come across a weirdness in using Safe with just the :base_core ops, using Perl 5.005_03. I have a sub foo with a prototype of `()' (takes no args), which I can use by calling just foo. But doing so in a Safe compartment with the reval method fails; I have to add brackets, or I get "glob value trapped by operation mask". Calling with brackets works, though.

Using the :default opset works. Which op do I need to add to :base_code to allow prototype lookup to work?

The enclosed code demonstrates:

#!/usr/local/bin/perl -w

use strict;
use Safe;

# Stuff from here will be shared into the Safe compartment
package Shared;

{
  my $n;
  sub foo() { ++$n };
}

package main;

my $cpt = new Safe;
$cpt->permit_only(':base_core');
$cpt->share_from( Shared => [qw( &foo )] );

print "foo returns ", Shared::foo, "\n"
  for (1..3);

sub safe_eval {
  my $q = shift;
  my $res = $cpt->reval($q);
  if ($@) {
    "ERROR: $@\n";
  }
  else {
    "$res\n";
  }
}

print "reval(foo) returns ", safe_eval('foo') for (1..3);
print "reval(foo()) returns ", safe_eval('foo()') for (1..3);
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