The following code seems to show that using "my" in a loop has a noticeable cost. I thought that maybe "it" would "see" how my was nested and just deal with it once. The output is: 
0.0232839584350586 my outside
0.0305099487304688 my inside

[download]
use Time::HiRes qw(time);
my ($i);
my $start = time;
{
  my $x;
  for $i (1..1e6) {
    $x = 1;
  }
}
my $end = time;
printf "%s my outside\n", $end - $start;

$start = time;
for $i (1..1e6) {
  my $x = 1;
}
$end = time;
printf "%s my inside\n", $end - $start;

[download]

In reply to "my" cost by Danny

Title:
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