sanitize_title
    applied to a post title by the sanitize_title function, after stripping out HTML tags. 

wordpress/wp-includes/taxonomy.php:		$value = apply_filters("pre_term_$field", $value, $taxonomy);

wordpress/wp-includes/default-filters.php:$filters = array('pre_term_slug');
wordpress/wp-includes/plugin.php:function apply_filters($tag, $value) {
wordpress/wp-includes/formatting.php:function sanitize_file_name( $name ) { // Like sanitize_title, but with periods
wordpress/wp-includes/formatting.php:function sanitize_title($title, $fallback_title = '') {
wordpress/wp-includes/formatting.php:	$title = apply_filters('sanitize_title', $title);
wordpress/wp-includes/taxonomy.php:		$args['query_var'] = sanitize_title_with_dashes($args['query_var']);
wordpress/wp-includes/taxonomy.php:			$args['rewrite']['slug'] = sanitize_title_with_dashes($taxonomy);
wordpress/wp-includes/taxonomy.php:		$value = sanitize_title($value);
wordpress/wp-includes/taxonomy.php:		$slug = sanitize_title($slug);
wordpress/wp-includes/taxonomy.php:	if ( '' === $slug = sanitize_title($term) )
wordpress/wp-includes/taxonomy.php:		$slug = sanitize_title($name);
wordpress/wp-includes/taxonomy.php:		$slug = sanitize_title($slug, $term_id);
wordpress/wp-includes/taxonomy.php:		$slug = sanitize_title($name);
wordpress/wp-includes/taxonomy.php:		$slug = sanitize_title($name, $term_id);

function add_filter($tag, $function_to_add, $priority = 10, $accepted_args = 1) {
	global $wp_filter, $merged_filters;

	$idx = _wp_filter_build_unique_id($tag, $function_to_add, $priority);
	$wp_filter[$tag][$priority][$idx] = array('function' => $function_to_add, 'accepted_args' => $accepted_args);
	unset( $merged_filters[ $tag ] );
	return true;
}



// Slugs
$filters = array('pre_term_slug');
foreach ( $filters as $filter ) {
	add_filter($filter, 'sanitize_title');
}

add_filter('sanitize_title', 'sanitize_title_with_dashes');


function sanitize_title_with_dashes($title) {
	$title = strip_tags($title);
	// Preserve escaped octets.
	$title = preg_replace('|%([a-fA-F0-9][a-fA-F0-9])|', '---$1---', $title);
	// Remove percent signs that are not part of an octet.
	$title = str_replace('%', '', $title);
	// Restore octets.
	$title = preg_replace('|---([a-fA-F0-9][a-fA-F0-9])---|', '%$1', $title);

	$title = remove_accents($title);
	if (seems_utf8($title)) {
		if (function_exists('mb_strtolower')) {
			$title = mb_strtolower($title, 'UTF-8');
		}
		$title = utf8_uri_encode($title, 200);
	}

	$title = strtolower($title);
	$title = preg_replace('/&.+?;/', '', $title); // kill entities
	$title = preg_replace('/[^%a-z0-9 _-]/', '', $title);
	$title = preg_replace('/\s+/', '-', $title);
	$title = preg_replace('|-+|', '-', $title);
	$title = trim($title, '-');

	return $title;
}