<?php
// Do not copy opening PHP tag above
// Add this code to your theme's functions.php file

// Add Previous/Next navigation to single listings
add_action( 'genesis_loop', 'wsm_add_listings_navigation' );
function wsm_add_listings_navigation() {

	// bail if we aren't on a single listing CPT
	if ( ! is_singular( 'listing' ) ) {
		return;
	}

	// Add the links
	echo '<div class="listing-nav previous">';
		previous_post_link( '%link', 'Previous Listing' );
	echo '</div>';
	echo '<div class="listing-nav next">';
		next_post_link( '%link', 'Next Listing' );
	echo '</div>';

}