#!/usr/bin/perl

use strict;
use warnings;

use vars '$global';
my $lexical;

$global  = 'outer';
$lexical = 'outer';

sub show {
    printf "\$global is '%s'; \$lexical is '%s'\n", $global, $lexical;
}

show;

{
    local $global = 'inner';
    my $lexical   = 'inner';
    show;
}

__END__
$global is 'outer'; $lexical is 'outer'
$global is 'inner'; $lexical is 'outer'