Hi, Can anyone tell me why this doesn't work when taint checking is turned on, but it does when it is off? I've read the perlsec stuff a few times, and don't see anything that resembles this situation. 
my $class = 'Classes::SomeChild';
if {$class->isa('Classes::SomeParent')) {
  my $object = $class->new();
  my $results = $object->doSomething();
}

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OK, to be honest, $class is actually a variable that *was* tainted, but has since been untainted (definitely - even checked with the is_taint sub in perlsec), but it is just a scalar as in the example. When taint checking is not enabled, this works perfectly. When it is on, the following line returns undef: 
$class->isa('Classes::SomeParent');

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Why is it so?

In reply to isa() and taint checking by webby

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