<?php
 
function slugify($text)
{
  // replace non letter or digits by -
  $text = preg_replace('~[^\pL\d]+~u', '-', $text);
 
  // transliterate
  $text = iconv('utf-8', 'us-ascii//TRANSLIT', $text);
 
  // remove unwanted characters
  $text = preg_replace('~[^-\w]+~', '', $text);
 
  // trim
  $text = trim($text, '-');
 
  // remove duplicate -
  $text = preg_replace('~-+~', '-', $text);
 
  // lowercase
  $text = strtolower($text);
 
  if (empty($text)) {
    return 'n-a';
  }
 
  return $text;
}
 
 
$str1 = "This is a test url - hyphen problem. When there is space before a character.";
$str2 = "";
 
 
echo slugify($str2);
 
 
 
 

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