Later, when using `$offset` (for example to show error messages), its value is not useful anymore since we would need an utf8 offset…
I suggest adding another var like :
```php
$offset    += $nextToken['length'];
$rawOffset += strlen($nextToken['value']);
```
and using
* `$rawOffset` as `$this->nextToken` argument
* `$offset` as `$tokenized['offset']`

Note : I primarily thought about adding both offset and rawOffset in `$tokenized`, but I don't think this is required, and it would increase memory consumption.