// The strongly typed collection class.
 class Names extends LJCCollectionBase
 {
   // Adds a string.
   // This method makes a string collection strongly typed.
   public function Add(string $text)
   {
     $retItem = $this->AddItem($text);
     return $retItem;
   }
 }
 
 // Indicates if a key already exists.
 private static function HasKey()
 {
   $names = new Names();
   $names->Add("First");
   $names->Add("Second");
   $names->Add("Third");
   $result = "";
   foreach ($names as $name)
   {
     if (strlen($result) > 0)
     {
       $result .= ",";
     }
     $result .= $name;
   }
 
   // result:
   // First,Second,Third;
 }