die "No such method $AUTOLOAD. Barfing\n"
      unless exists $self->{$field};
  if ($self->{$field}{editable}) {
    *$AUTOLOAD = eval <<ENDSUB;
sub {
   my \$self = shift;
   \$self->{$field}{value} = shift if \@_;
   \$self->{$field}{value};
}
ENDSUB

  } else {
    *$AUTOLOAD = eval <<ENDSUB2;
sub {
    my \$self = shift;
    die "Can't modify readonly field '$field'" if \@_;
    \$self->{$field}{value};
}
ENDSUB2

  }
  goto &$AUTOLOAD;