pocketmine\utils\UUID::toBinary PHP Method

    public function toBinary()
    {
        return Binary::writeInt($this->parts[0]) . Binary::writeInt($this->parts[1]) . Binary::writeInt($this->parts[2]) . Binary::writeInt($this->parts[3]);
    }

 /**
  * @param UUID $id
  * @return Recipe
  */
 public function getRecipe(UUID $id)
 {
     $index = $id->toBinary();
     return isset($this->recipes[$index]) ? $this->recipes[$index] : null;
 }