wp_get_canonical_url( int|WP_Post $post = null ): string|false

4059function wp_get_canonical_url( $post = null ) {4060	$post = get_post( $post );4061 4062	if ( ! $post ) {4063		return false;4064	}4065 4066	if ( 'publish' !== $post->post_status ) {4067		return false;4068	}4069 4070	$canonical_url = get_permalink( $post );4071 4072	// If a canonical is being generated for the current page, make sure it has pagination if needed.4073	if ( get_queried_object_id() === $post->ID ) {4074		$page = get_query_var( 'page', 0 );4075		if ( $page >= 2 ) {4076			if ( ! get_option( 'permalink_structure' ) ) {4077				$canonical_url = add_query_arg( 'page', $page, $canonical_url );4078			} else {4079				$canonical_url = trailingslashit( $canonical_url ) . user_trailingslashit( $page, 'single_paged' );4080			}4081		}4082 4083		$cpage = get_query_var( 'cpage', 0 );4084		if ( $cpage ) {4085			$canonical_url = get_comments_pagenum_link( $cpage );4086		}4087	}4088 4089	/**4090	 * Filters the canonical URL for a post.4091	 *4092	 * @since 4.6.04093	 *4094	 * @param string  $canonical_url The post's canonical URL.4095	 * @param WP_Post $post          Post object.4096	 */4097	return apply_filters( 'get_canonical_url', $canonical_url, $post );4098}