foreach my $section ( @_ ) { ... } doesn't copy value from @_ to $section. In the loop the variable $section is merely an alias to a currently selected element in @_ array. You can even modify @_ array by assigning a new value to $section. Example: 

# adds 1 to all elements of array
foreach my $elem (@arr) {
    $elem ++;
}

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Ilya Martynov, ilya@iponweb.net
CTO IPonWEB (UK) Ltd
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In reply to Re: Re: Re: Optimizing the bejeezus out of a sub by IlyaM
in thread Optimizing the bejeezus out of a sub by sgifford

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