Wordpress: globally-isolating a page's slug.

slug.php

function get_the_slug( $id=null ){
  if( empty($id) ):
    global $post;
    if( empty($post) )
      return ''; // No global $post var available.
    $id = $post->ID;
  endif;

  $slug = basename( get_permalink($id) );
  return $slug;
}

/* Actually returns slug kinda */

/**
 * Display the page or post slug
 *
 * Uses get_the_slug() and applies 'the_slug' filter.
 */
function the_slug( $id=null ){
  echo apply_filters( 'the_slug', get_the_slug($id) );
}

/* This is how to use slug */
/* <?php the_slug(); ?> */