[Plugin: Posts 2 Posts] Nested loops relating to one CPT

You can use each_connected():

https://github.com/scribu/wp-posts-to-posts/wiki/Looping-The-Loop

Hi Arlo. Try this in single-article.php:

// get writers connected to blurbs connected to this article
$writers = p2p_type( 'blurb_to_writer' )->set_direction( 'to' )->get_related( $post );

// get blurbs connected to this article (by way of being connected to a related writer so that we can use p2p_distribute_connected to merge the arrays)
$blurbs = p2p_type( 'blurb_to_writer' )->set_direction( 'from' )->get_related( $post );

// match the blurbs with the writers and store in each writer
p2p_distribute_connected( $writers->posts, $blurbs->posts, 'blurbs' );

echo '<ul>';
foreach( $writers->posts as $writer ):
	echo '<li>';
	echo '<a href="' . get_permalink($writer) . '">' . get_the_title($writer) . '</a>'; // display the title of this writer (with a permalink)
	p2p_list_posts( $writer->blurbs ); // list blurbs for this writer
	echo '</li>';
endforeach;
echo '</ul>';

This should display writers connected to blurbs that are connected to this article. It ignores the writer to article relationship since I assumed that would be for specifying the author or writers the article talks about, or something ultimately unrelated to blurbs.

scribu- thanks for that, I did actually go through that page, but really couldn’t make sense of it.
dlukez, thanks so much for the snippet. The loop nesting is breaking a bit somehow:

<ul>
  <li>Writer1</li>
  <li>Writer1
    <ul>
      <li>Blurb A</li>
      <li>Blurb B</li>
    </ul>
  </li>
</ul>

Not only is “Writer1” repeating but I should not be seeing “blurb b”, as that is connected to another article. It is connected to Writer1, however, so it seems the filtering by the main article loop isn’t working.

But one thing I should add, is that p2p_list_posts() won’t work for me in this instance, as I need to output custom content for each writer/blurb grouping, not just a link list. I’m wondering if what I want to do is just too complex in general.

Yeah I find each_connected() confusing in some cases. Could you clarify the relationships between Blurb, Writer and Article? I don’t really understand how your connections are set up so I probably have mine set up differently!

These are my connections:

p2p_register_connection_type( array(
		'name' => 'blurb_writer',
		'from' => 'blurb',
		'to' => 'writer'
	) );

	p2p_register_connection_type( array(
		'name' => 'blurb_article',
		'from' => 'blurb',
		'to' => 'articles'
	) );

	p2p_register_connection_type( array(
		'name' => 'writer_article',
		'from' => 'writer',
		'to' => 'articles'
	) );

I’ve been testing in parallel using just taxonomies to get the job done, but of course this isn’t ideal for the user (they’d need to manually add taxes of the same kind in multiple tax-types to achieve what p2p *should* alone).

So you want to display writers connected to the article, then blurbs connected to both that article AND each writer who is also connected to that article?

A short description of what each content type and relationship means, then why you want to display them on the article might help. e.g. “a blurb is an excerpt for one article” (blurb->article).

I think p2p can do what you want, it’s more a matter of working out the best way to fit things together.