It's not re-allocating memory each time through the loop. You can test that by doing this: 
    my $count = 1;
    while (my $x = $count) {
        print \$x, "\n";
        last if ++$count > 5;
    }

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If you run that, you should get something like: 
    SCALAR(0x80e4aa8)
    SCALAR(0x80e4aa8)
    SCALAR(0x80e4aa8)
    SCALAR(0x80e4aa8)
    SCALAR(0x80e4aa8)

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Each time through the loop $x is at the same memory location. So it's not re-allocating memory.

As tilly mentions in his post, Perl does have to do *some* extra things--but re-allocating memory isn't one of them. :)

In reply to RE: Re: redeclaring variables with 'my' by btrott
in thread redeclaring variables with 'my' by tune

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