use Devel::Peek;

our $foo;
Dump $foo;
Dump $main::foo;

__END__
SV = NULL(0x0) at 0x24bfdc4
  REFCNT = 1
  FLAGS = ()
SV = NULL(0x0) at 0x24bfdc4
  REFCNT = 1
  FLAGS = ()

##</code><code>##

use strict;

{
  our $foo = 'foo';
  our $bar = 'bar';
}
{
  our $foo;
  print $foo;
  print $main::bar;
}

__END__
foobar