package GenObj;

my %methods = (
  name => sub { $_[0]{DATA}{name} },
  setname => sub { $_[0]{DATA}{name} = $_[1] },
  # ...
);

sub new {
  my ($class) = @_;
  bless { DATA => {}, METHODS => {%methods} }, $class;
}

AUTOLOAD {
  (my $method = $AUTOLOAD) =~ s/.*:://;
  $_[0]{METHODS}{$method} ?
    goto &{$_[0]{METHODS}{$method}} :
    die "unsupported method $method for object";
}

package main;

$foo = GenObj->new;
$foo->setname("Jeff");
print $foo->name;