I'm trying to figure out exactly what opcode gives you the functionality to do quoted string interpretation, eg when you set $foo='FOO!'; and then print "$foo"; -- what changes "$foo" into 'FOO!'. So, I threw together this script... and it ain't workin. Anyone have any experience with the safe module and Text::Template? 
#!/usr/bin/perl
use Opcode;
use Text::Template;
use Safe;
my @names = Opcode::opset_to_ops(Opcode::full_opset);

foreach my $name (@names)
{
  my (@feh);
  my ($cmptmt);
  undef $cmptmt;
  print "trying name $name..\t\t";
  $cmptmt = new Safe;
  push @feh,$name;
  $cmptmt->permit_only(@feh);
  $Journal::true = 10;
  my $template_text = '{$true}';
  my $template = new Text::Template (TYPE   => 'STRING',
                                     SOURCE => $template_text,
                                     SAFE   => $cmptmt);
  my $return_text = $template->fill_in(PACKAGE => Journal);
  if ($return_text eq "10")
  {
    print "return text is ok... ";
  $cmptmt1 = new Safe;
  $cmptmt1->permit_only(@feh);

    my $template_text1 = '{open(PASSWD,"/etc/passwd");read(PASSWD,$_,1
+,0);print}';
    $template1 = new Text::Template (TYPE   => 'STRING',
                                    SOURCE => $template_text1,
                                    SAFE   => $cmptmt1);
    if ($return_text1 = $template1->fill_in(PACKAGE => Journal) == 1)
    { print "Um, ok?\n"; }
    else
    { print "Bad!!\n"; }
  }
}

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In reply to use Safe; by da w00t

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