package Help;

use strict;
use warnings;

sub new {
   my ($class, %args) = @_;

   my $self = {};
   bless $self, $class;

   # populate
   $self->{attributes} = [qw(foo boo)];
   $self->$_($args{$_}) for @{$self->{attributes}};

   return $self;
}

sub foo {
   my ($self, $value) = @_;

   if (defined $value) {
      $self->{foo} = $value;
      return 1;
   } else {
      return $self->{foo}; # shouldn't this autoviv?
   }
}

sub boo {
   my ($self, $value) = @_;

   if (defined $value) {
      $self->{boo} = $value;
      return 1;
   } else {
      return $self->{boo};
   }
}

package main;

use Data::Dumper;

# no autoviv? what?
my $obj_01 = Help->new();
print Dumper($obj_01);

# we set values - that works
my $obj_02 = Help->new(foo => '', boo => "value");
print Dumper($obj_02);

# again, no autoviv (I expect it to be the same as 01
# but am still surprised there is no autoviv happening)
my $obj_03 = Help->new(foo => undef, boo => undef);
print Dumper($obj_03);

1;