No there's not, the QIntValidator gets the QLineEdit as parent and thus it will get deleted at the same time as the widget.

No leak per se but indeed, if you start to change the validator frequently you'll have a bunch of unused objects lying around that will get deleted when the widget is destroyed.

I'd recommend calling deleteLater so you ensure that if there are events pending nothing goes wrong.

@kshegunov
Allright, thanks for the help.

@Kaluss said:

but do You maybe know whats that parameter really do?

It's suppose to be "cursor position", but in case of regexp validator it's really a useless parameter to satisfy the interface of QValidator. It gets set to the length of the string if the regexp validator doesn't find a match.

Thank you for your help

I do :)

However, you don't need to build Qt 5.5 to build it, you can use your current Qt version

@mrdebug
If you are using only uppercase letters in QRegExp you should be fine. E.g. "[IO]{1,1}" shall match only an uppercase 'I' or an uppercase 'O'.