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function is not described

get_tag_regex() WP 3.6.0

Return RegEx body to liberally match an opening HTML tag.

Matches an opening HTML tag that:

  1. Is self-closing or
  2. Has no body but has a closing tag of the same name or
  3. Contains a body and a closing tag of the same name

Note: this RegEx does not balance inner tags and does not attempt to produce valid HTML

No Hooks.

Return

String. Tag RegEx.

Usage

get_tag_regex( $tag );
$tag(string) (required)
An HTML tag name. Example: 'video'.

Code of get tag regex: wp-includes/functions.php VER 5.1.1

<?php
function get_tag_regex( $tag ) {
	if ( empty( $tag ) ) {
		return;
	}
	return sprintf( '<%1$s[^<]*(?:>[\s\S]*<\/%1$s>|\s*\/>)', tag_escape( $tag ) );
}