new rel_canonical function

gistfile1.aw

<?php

// this would replace the rel_canonical function in wp-includes/link-template.php

/**
 * Output rel=canonical
 *
 * @package WordPress
 * @since 2.9.0
*/
function rel_canonical() {
	$link = false;
	
	if ( is_singular() ) {
		$link = get_permalink( get_queried_object() );
		if ( $page = get_query_var('page') && 1 != $page )
			$link = user_trailingslashit( trailingslashit( $link ) . get_query_var( 'page' ) );
	} else {
		if ( is_front_page() ) {
			$link = trailingslashit( get_bloginfo('url') );
		} else if ( is_home() && get_option('show_on_front') == "page" ) {
			$link = get_permalink( get_option( 'page_for_posts' ) );
		} else if ( is_tax() || is_tag() || is_category() ) {
			$term = get_queried_object();
			$link = get_term_link( $term, $term->taxonomy );
		} else if ( is_post_type_archive() ) {
			$link = get_post_type_archive_link( get_post_type() );
		} else if ( is_archive() ) {
			if ( is_date() ) {
				if ( is_day() ) {
					$link = get_day_link( get_query_var('year'), get_query_var('monthnum'), get_query_var('day') );
				} else if ( is_month() ) {
					$link = get_month_link( get_query_var('year'), get_query_var('monthnum') );
				} else if ( is_year() ) {
					$link = get_year_link( get_query_var('year') );
				}						
			}
		}
		
		if ( $link && $paged = get_query_var('paged') && $paged > 1 ) {
			global $wp_rewrite;
			$link = user_trailingslashit( trailingslashit( $link ) . trailingslashit( $wp_rewrite->pagination_base ) . $paged );
		}
	}

	$link = apply_filters( 'rel_canonical', $link );
	
	if ( $link )
		echo "<link rel='canonical' href='$link' />\n";
}