package Foo;
use strict;
use base 'Exporter';
@Foo::EXPORT_OK = qw(foo);
 
  
sub foo {
  print "Foo\n";
}
1;

package Bar;
use strict;
use Foo qw(foo);
 
sub bar {
  foo();
  print "Bar\n";
}
1;


 package Something;
 use strict;
 
 use Bar;
 # This call will fail.
 foo();