DataMapper ORM v1.8.1

[eluser]WanWizard[/eluser]
If you're looking to store tree structures, you might want to have a look at the nestedsets extension, included in the Datamapper distribution. See http://datamapper.wanwizard.eu/pages/ext...dsets.html for more information.

If you insist on using Adjacency lists:

Code:

class Mylist extends DataMapper {
    $has_many = array(
        'parent' => array(
            'class' => 'mylist',
            'other_field' => 'mylist',
        ),
        'mylist' => array(
            'other_field' => 'parent',
        )
    );
}

You'll have to write the methods to navigate through the list yourself, where the nestedsets extension includes all methods to deal with parents, children and siblings...