GraphQL\Language\Lexer::readName PHP Method

    private function readName($position, $line, $col, Token $prev)
    {
        $body = $this->source->body;
        $bodyLength = $this->source->length;
        $end = $position + 1;
        while ($end !== $bodyLength && ($code = Utils::charCodeAt($body, $end)) && ($code === 95 || $code >= 48 && $code <= 57 || $code >= 65 && $code <= 90 || $code >= 97 && $code <= 122)) {
            ++$end;
        }
        return new Token(Token::NAME, $position, $end, $line, $col, $prev, mb_substr($body, $position, $end - $position, 'UTF-8'));
    }