wp_query->have_comments();
}

/**
 * Iterate comment index in the comment loop.
 *
 * @since 2.2.0
 *
 * @global WP_Query $wp_query Global WP_Query instance.
 *
 * @return object
 */
function the_comment() {
	global $wp_query;
	return $wp_query->the_comment();
}

/**
 * Redirect old slugs to the correct permalink.
 *
 * Attempts to find the current slug from the past slugs.
 *
 * @since 2.1.0
 */
function wp_old_slug_redirect() {
	if ( is_404() && '' !== get_query_var( 'name' ) ) {
		// Guess the current post_type based on the query vars.
		if ( get_query_var( 'post_type' ) ) {
			$post_type = get_query_var( 'post_type' );
		} elseif ( get_query_var( 'attachment' ) ) {
			$post_type = 'attachment';
		} elseif ( get_query_var( 'pagename' ) ) {
			$post_type = 'page';
		} else {
			$post_type = 'post';
		}

		if ( is_array( $post_type ) ) {
			if ( count( $post_type ) > 1 ) {
				return;
			}
			$post_type = reset( $post_type );
		}

		// Do not attempt redirect for hierarchical post types
		if ( is_post_type_hierarchical( $post_type ) ) {
			return;
		}

		$id = _find_post_by_old_slug( $post_type );

		if ( ! $id ) {
			$id = _find_post_by_old_date( $post_type );
		}

		/**
		 * Filters the old slug redirect post ID.
		 *
		 * @since 4.9.3
		 *
		 * @param int $id The redirect post ID.
		 */
		$id = apply_filters( 'old_slug_redirect_post_id', $id );

		if ( ! $id ) {
			return;
		}

		$link = get_permalink( $id );

		if ( get_query_var( 'paged' ) > 1 ) {
			$link = user_trailingslashit( trailingslashit( $link ) . 'page/' . get_query_var( 'paged' ) );
		} elseif( is_embed() ) {
			$link = user_trailingslashit( trailingslashit( $link ) . 'embed' );
		}

		/**
		 * Filters the old slug redirect URL.
		 *
		 * @since 4.4.0
		 *
		 * @param string $link The redirect URL.
		 */
		$link = apply_filters( 'old_slug_redirect_url', $link );

		if ( ! $link ) {
			return;
		}

		wp_redirect( $link, 301 ); // Permanent redirect
		exit;
	}
}

/**
 * Find the post ID for redirecting an old slug.
 *
 * @see wp_old_slug_redirect()
 *
 * @since 4.9.3
 * @access private
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $post_type The current post type based on the query vars.
 * @return int $id The Post ID.
 */
function _find_post_by_old_slug( $post_type ) {
	global $wpdb;

	$query = $wpdb->prepare( "SELECT post_id FROM $wpdb->postmeta, $wpdb->posts WHERE ID = post_id AND post_type = %s AND meta_key = '_wp_old_slug' AND meta_value = %s", $post_type, get_query_var( 'name' ) );

	// if year, monthnum, or day have been specified, make our query more precise
	// just in case there are multiple identical _wp_old_slug values
	if ( get_query_var( 'year' ) ) {
		$query .= $wpdb->prepare( " AND YEAR(post_date) = %d", get_query_var( 'year' ) );
	}
	if ( get_query_var( 'monthnum' ) ) {
		$query .= $wpdb->prepare( " AND MONTH(post_date) = %d", get_query_var( 'monthnum' ) );
	}
	if ( get_query_var( 'day' ) ) {
		$query .= $wpdb->prepare( " AND DAYOFMONTH(post_date) = %d", get_query_var( 'day' ) );
	}

	$id = (int) $wpdb->get_var( $query );

	return $id;
}

/**
 * Find the post ID for redirecting an old date.
 *
 * @see wp_old_slug_redirect()
 *
 * @since 4.9.3
 * @access private
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $post_type The current post type based on the query vars.
 * @return int $id The Post ID.
 */
function _find_post_by_old_date( $post_type ) {
	global $wpdb;

	$date_query = '';
	if ( get_query_var( 'year' ) ) {
		$date_query .= $wpdb->prepare( " AND YEAR(pm_date.meta_value) = %d", get_query_var( 'year' ) );
	}
	if ( get_query_var( 'monthnum' ) ) {
		$date_query .= $wpdb->prepare( " AND MONTH(pm_date.meta_value) = %d", get_query_var( 'monthnum' ) );
	}
	if ( get_query_var( 'day' ) ) {
		$date_query .= $wpdb->prepare( " AND DAYOFMONTH(pm_date.meta_value) = %d", get_query_var( 'day' ) );
	}

	$id = 0;
	if ( $date_query ) {
		$id = (int) $wpdb->get_var( $wpdb->prepare( "SELECT post_id FROM $wpdb->postmeta AS pm_date, $wpdb->posts WHERE ID = post_id AND post_type = %s AND meta_key = '_wp_old_date' AND post_name = %s" . $date_query, $post_type, get_query_var( 'name' ) ) );

		if ( ! $id ) {
			// Check to see if an old slug matches the old date
			$id = (int) $wpdb->get_var( $wpdb->prepare( "SELECT ID FROM $wpdb->posts, $wpdb->postmeta AS pm_slug, $wpdb->postmeta AS pm_date WHERE ID = pm_slug.post_id AND ID = pm_date.post_id AND post_type = %s AND pm_slug.meta_key = '_wp_old_slug' AND pm_slug.meta_value = %s AND pm_date.meta_key = '_wp_old_date'" . $date_query, $post_type, get_query_var( 'name' ) ) );
		}
	}

	return $id;
}

/**
 * Set up global post data.
 *
 * @since 1.5.0
 * @since 4.4.0 Added the ability to pass a post ID to `$post`.
 *
 * @global WP_Query $wp_query Global WP_Query instance.
 *
 * @param WP_Post|object|int $post WP_Post instance or Post ID/object.
 * @return bool True when finished.
 */
function setup_postdata( $post ) {
	global $wp_query;

	if ( ! empty( $wp_query ) && $wp_query instanceof WP_Query ) {
		return $wp_query->setup_postdata( $post );
	}

	return false;
}