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function is not described

get_boundary_post_rel_link() WP 2.8.0

Deprecated in 3.3.0. It is no longer supported and can be removed in future releases. It is recommended to replace this function with the same one.

Get boundary post relational link.

Can either be start or end post relational link.

Hooks from the function
Return

String.

Usage

get_boundary_post_rel_link( $title, $in_same_cat, $excluded_categories, $start );
$title(string)
Link title format.
Default: '%title'
$in_same_cat(true/false)
Whether link should be in a same category.
Default: false
$excluded_categories(string)
Excluded categories IDs.
Default: ''
$start(true/false)
Whether to display link to first or last post.
Default: true

Changelog

Since DEL 3.3.0 Introduced.

Code of get boundary post rel link: wp-includes/deprecated.php WP 5.2.2

<?php
function get_boundary_post_rel_link($title = '%title', $in_same_cat = false, $excluded_categories = '', $start = true) {
	_deprecated_function( __FUNCTION__, '3.3.0' );

	$posts = get_boundary_post($in_same_cat, $excluded_categories, $start);
	// If there is no post stop.
	if ( empty($posts) )
		return;

	// Even though we limited get_posts to return only 1 item it still returns an array of objects.
	$post = $posts[0];

	if ( empty($post->post_title) )
		$post->post_title = $start ? __('First Post') : __('Last Post');

	$date = mysql2date(get_option('date_format'), $post->post_date);

	$title = str_replace('%title', $post->post_title, $title);
	$title = str_replace('%date', $date, $title);
	$title = apply_filters('the_title', $title, $post->ID);

	$link = $start ? "<link rel='start' title='" : "<link rel='end' title='";
	$link .= esc_attr($title);
	$link .= "' href='" . get_permalink($post) . "' />\n";

	$boundary = $start ? 'start' : 'end';
	return apply_filters( "{$boundary}_post_rel_link", $link );
}