accessor

package cm3;
sub new { bless $_[1], $_[0] }

use lib "tests";

# comment/uncomment one or the other:
use Accessor_maker;
# sub foo { $_[0]->{ 'foo' } }

package main;

sub test {
  my $self = shift;

  print 'un' unless defined $self->foo;
  print "defined\n";

  my $foo = $self->foo;
  print 'un' unless defined $foo;
  print "defined\n";
}

test( cm3->new({}) );
test( cm3->new({foo => 1}) );