twentythirteen_post_nav()

530	function twentythirteen_post_nav() {531		global $post;532 533		// Don't print empty markup if there's nowhere to navigate.534		$previous = ( is_attachment() ) ? get_post( $post->post_parent ) : get_adjacent_post( false, '', true );535		$next     = get_adjacent_post( false, '', false );536 537		if ( ! $next && ! $previous ) {538			return;539		}540		?>541		<nav class="navigation post-navigation">542		<h1 class="screen-reader-text">543			<?php544			/* translators: Hidden accessibility text. */545			_e( 'Post navigation', 'twentythirteen' );546			?>547		</h1>548		<div class="nav-links">549 550			<?php previous_post_link( '%link', _x( '<span class="meta-nav">&larr;</span> %title', 'Previous post link', 'twentythirteen' ) ); ?>551			<?php next_post_link( '%link', _x( '%title <span class="meta-nav">&rarr;</span>', 'Next post link', 'twentythirteen' ) ); ?>552 553		</div><!-- .nav-links -->554	</nav><!-- .navigation -->555		<?php556	}