protected function readWord()
    {
        $word = '';

        // Try to read the word
        while (($char = $this->inputStream->readCurrent()) !== null) {
            if ($this->isLetter($char)) {
                $word .= $char;
            } else {
                break;
            }

            // Just move the cursor to the next position
            $this->inputStream->readNext();
        }

        return $word;
    }