But they often can achieve the same result. And usually people use them without even noticing the difference... And ther is a difference. . . a quick example: 
use Time::HiRes qw(gettimeofday);
$start_time = gettimeofday();
$global_variable = "hello!";

for ($i = 0; $i < 10000000; $i++) {
        # replace this with "my"
        local $global_variable = "redefined. . ";
}
print gettimeofday - $start_time." seconds\n";
print "$global_variable\n";

[download]
outputs 
31.4016380310059 seconds
hello!

[download]
and 
14.1771370172501 seconds
hello!

[download]
when using "my" instead.

In reply to Re: is 'my' that much faster than 'local'? by twerq
in thread is 'my' that much faster than 'local'? by gregw

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