I use array objects with constants for the indexes, so I don't have that problem.

use constant FIRST_IDX => __PACKAGE__->SUPER::NEXT_IDX();
use constant IDX_NAME  => FIRST_IDX + 0;
use constant IDX_ATTS  => FIRST_IDX + 1;
use constant NEXT_IDX  => FIRST_IDX + 2;

sub name {
   my ($self) = @_;
   return $self->[IDX_NAME];
}
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Something similar could be used for hashes.

use constant IDX_NAME => 'NAME';
use constant IDX_ATTS => 'ATTS';

sub name {
   my ($self) = @_;
   return $self->{IDX_NAME()};
}
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As long as you always put the (), errors will always be caught (at run-time). A typo would lead to an error message like Undefined subroutine &main::IDX_NAMES called