my $foo = 'bar';

##</code><code>##

#!/usr/bin/perl
use strict;
use warnings;

sub foo {
  my $bar = 'baz';
}

foo();

print $bar; # error

##</code><code>##

#!/usr/bin/perl
use strict;
use warnings;

my $bar = 'baz';

sub foo {
  $bar = 'qux';
}

foo();

print $bar; # prints 'qux'