Slugify a string

slugify.php

<?php
/**
 *  Converts text from
 *    "thing + (Beep) $%^boop"
 *  to
 *    "thing-beep-boop"
 * 
 * @author Richard de Wit
 * @link https://gist.github.com/richarddewit/06692629a1503f931ff9d54002ffc14e
 *
 * @param  string $text  input text
 *
 * @return string  slugified text
 */
function slugify($text) {
  // Replace non letter or digits by -
  $text = preg_replace('/[^\pL\d]+/u', '-', $text);
  // Transliterate letters with diacritics, umlauts, etc. to plain letters
  $text = iconv('utf-8', 'us-ascii//TRANSLIT', $text);
  // Remove unwanted characters
  $text = preg_replace('/[^-\w]+/', '', $text);
  // Remove duplicate hyphens
  $text = preg_replace('/-+/', '-', $text);
  // Trim leading and trailing hyphens
  $text = trim($text, '-');
  // Lowercase
  $text = strtolower($text);
  if (empty($text)) {
    return '';
  }
  return $text;
}