$ perl -TMScalar::Util=tainted -wE '$x = $0; say tainted $x; ($x) = ke
+ys %{{$x => 1}}; say tainted $x'
1
0
$ perl -TMScalar::Util=tainted -wE '$x = $0; say tainted $x; $x = join
+ "", map {chr ord substr $x, $_, 1} 0 .. length($x) - 1; say tainted 
+$x'
1
0
$ perl -TMScalar::Util=tainted -wE '$x = $0; say tainted $x; $x = lc $
+x; say tainted $x'  # May change the case of $x
1
0
$ perl -TMScalar::Util=tainted -wE '$x = $0; say tainted $x; $x = eval
+ qq["${\quotemeta $x}"] or die; say tainted $x'
1
0
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