simple_orm.php

<?php

$query = RelationShipQuery::new(
    'select * from `posts` where id = :id',
    function (array $record) {
        return new Post($record['id'], $record['title'], $record['body'], $record['author'], $record['comments']);
    }, 
    [
        'author' => PostBelongsToAuthor::hydratedBy(
            function (array $record) {
                return new Author($record['id'], $record['name']);
            }
         ),
        'comments' => PostHasManyComments::hydratedBy(
            function (array $record) {
                return new Comment(intval($record['id']), intval($record['post_id']), $record['title'], $record['body']);
            },
            [
                'author' => CommentBelongsToAuthor::hydratedBy(
                    function (array $record) {
                        return new Author(intval($record['id']), $record['name']);
                    }
                ),
            ]
        ),
    ]
);

$entity = $query->exec(['id' => 1]);