# Example 1... The best pre-Perl v5.6.0 way.
package foobar;
use strict;
use warnings;
use vars qw(@ISA @EXPORT);
@ISA = qw(Exporter);
@EXPORT = qw(foo bar);

# Example 2... The best Perl v5.6.0 + way.
package foobar;
use strict;
use warnings;
our @ISA = qw(Exporter);
our @EXPORT = qw(foo bar);

# Example 3... The 'base' way.
package foobar;
use strict;
use warnings;
use base qw(Exporter);
# But you still have to either 'use vars' or 'our' for the 
# export list @EXPORT.
our @EXPORT = qw(foo bar);