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function is not described

parent_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.

Display relational link for parent item

No Hooks.

Return

Nothing (null).

Usage

parent_post_rel_link( $title );
$title(string)
Link title format.
Default: '%title'

Code of parent post rel link: wp-includes/deprecated.php VER 5.0.3

<?php
function parent_post_rel_link( $title = '%title' ) {
	_deprecated_function( __FUNCTION__, '3.3.0' );

	echo get_parent_post_rel_link($title);
}