use warnings;
   use strict;
   package My::Mondo::Class;

   # This class is defined in multiple files - see
   use My::Mondo::Class_1;
   use My::Mondo::Class_2;
   use My::Mondo::Class_3;

##</code><code>##

use strict;
use warnings;
package My::Mondo::Class;

# methods and variable initializations that depend only
# on stuff declared in My::Mondo::Class or earlier parts
# in the sequence, i.e. if this is My::Mondo::Class_2 then
# it only references variables and methods in
# My::Mondo::Class and My::Mondo::Class_1

##</code><code>##

#Foo.pm
use strict;
use warnings;
package Foo;
use Foo_1.pm;
use Foo_2.pm;

# Foo_1.pm
use strict;
use warnings;
package Foo;

my $HELLO;
our $GOODBYE;
sub hello { return "Hi!"; }

# Foo_2.pm
use strict;
use warnings;
package Foo;          #note: also package Foo

#$HELLO='Bonjour'           #compiler complains - see below for why
$Foo::HELLO='Bonjour';       #this is OK - see below for why

#$GOODBYE='Au revoir'        #compiler complains - see below for why
$Foo::GOODBYE='Au revoir';   #this is OK - see below for why

# calling hello() without qualification is OK, so long
# as the package is Foo (which it is)

print hello() . ": Hello=$Foo::HELLO, Goodbye=$Foo::GOODBYE\n";