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function is not described

permalink_anchor() WP 0.71

Displays the permalink anchor for the current post.

The permalink mode title will use the post title for the 'a' element 'id' attribute. The id mode uses 'post-' with the post ID for the 'id' attribute.

No Hooks.

Return

Nothing (null).

Usage

permalink_anchor( $mode );
$mode(string)
Permalink mode. Accepts 'title' or 'id'.
Default: 'id'

Code of permalink anchor: wp-includes/link-template.php VER 5.1.1

<?php
function permalink_anchor( $mode = 'id' ) {
	$post = get_post();
	switch ( strtolower( $mode ) ) {
		case 'title':
			$title = sanitize_title( $post->post_title ) . '-' . $post->ID;
			echo '<a id="' . $title . '"></a>';
			break;
		case 'id':
		default:
			echo '<a id="post-' . $post->ID . '"></a>';
			break;
	}
}