As for me, Scalar::Util has more natural way to detect tainted variables 

perldoc Scalar::Util|grep taint

        use Scalar::Util qw(blessed dualvar isweak readonly refaddr re
+ftype tainted weaken isvstring looks_like_number set_prototype);
    tainted EXPR
        Return true if the result of EXPR is tainted
            $taint = tainted("constant");       # false
            $taint = tainted($ENV{PWD});        # true if running unde
+r -T

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In reply to Re: Please explain this tainting behaviour by ccn
in thread Please explain this tainting behaviour by Anonymous Monk

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