QPaintEvent syntax question

[last2kn0]

I just have a simple question about the syntax of writing a paintEvent handler.
Specifically, I have seen in many places when writing the event handler, the event pointer is commented out in the parameter list like this:

Class::paintEvent(QPaintEvent * /* event */)

Class::paintEvent(QPaintEvent * /* event */)

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Why is this done? I have compiled it with and without the comments and it has performed the same way. I haven't found any explanation for this.

Thanks !

[jpn]

The result of

void Class::paintEvent(QPaintEvent* /* event */)
{
    ...
}

void Class::paintEvent(QPaintEvent* /* event */)
{
    ...
}

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and

void Class::paintEvent(QPaintEvent* event)
{
    Q_UNUSED(event);
}

void Class::paintEvent(QPaintEvent* event)
{
    Q_UNUSED(event);
}

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is the same; the compiler won't complain about an unused parameter. Although the latter is more readable, isn't it?

[last2kn0]

Yeahhh, thats what I was thinking it was about. I didn't get any compiler complaints so it just made me wonder. Thanks a lot for the quick reply. Sometimes those little things that I don't know just bother me!

Thanks again

[wysota]

I don't think it is more readable. It's just another convention. And the first version will compile faster :P

[jpn]

I don't think it is more readable. It's just another convention. And the first version will compile faster :P

Maybe not for you, but just imagine the difference when someone not so familiar with C++ ends up maintaining that application.

[wysota]

As long as you don't remove the parameter name and just surround it with a comment, the readability shouldn't suffer much. But of course everybody has his/her own ways. I tend to use Q_UNUSED myself too.