package Foo;
our $bar = 'some default';  
sub new { bless {} }
sub bar { shift; $bar = shift if @_; $bar }

package main; 
my $obj = Foo->new;
print $obj->bar, "\n";
$obj->bar('something else');
print $obj->bar, "\n";

##</code><code>##

package Foo; 
our $bar = 'some default'; 

package main; 
print $Foo::bar, "\n";
$Foo::bar = 'something else';
print $Foo::bar, "\n";

##</code><code>##

package Foo; 
my $bar = 'some default'; 
sub bar {
    $bar = shift if @_; 
    return $bar;
}

##</code><code>##

package Foo;
my $bar = 'some default'; 
sub bar_ref {
    return \$bar; 
}

##</code><code>##

package Foo; 
my $bar = 'some default'; 
sub bar : lvalue {
  $bar;
}

##</code><code>##

 print Foo::bar, "\n"; 
Foo::bar = 'something else'; 
print Foo::bar;

##</code><code>##

package Foo; 
{ 
    my $bar = 'some default'; 
    sub bar : lvalue { $bar }
}