[Interest] What don't you like about Qt?

[Rob Allan]

> Enter OOP. In classic OOP there are no function calls, you just send
messages to object, and object dispatches
> them "somehow"

I don't think that sort of anonymous, decoupled messaging is the definition
of OOP. It is perhaps a description of the Observer Pattern, where the
"publisher" has no idea what "subscribers" might be out there. But even
then, in most OO languages, this is implemented through strongly-typed
interfaces - so that if you tried to "publish" a message that wasn't
defined, you would get a compile error. Most OO languages - Smalltalk, C++
C#, etc - are strongly typed and have robust compile-time checking, so you
can't just accidentally type the wrong name in a method call or property
access, and get no error. JavaScript is totally wild west in this regard -
you can pretty much type anything and it won't complain. This is not an
attribute of OO, it is an attribute of JavaScript.

> Don't you have unit tests?

Yes. But which is better, to be forced to use an inherently error-prone
language (JavaScript) and rely on unit tests to clean up the mess, or to
use a robust modern language (C++) and have less bugs to find and fix in
the first place?

Rob

On Wed, Sep 28, 2016 at 10:43 AM, Konstantin Tokarev <annulen at yandex.ru>
wrote:

>
>
> 28.09.2016, 00:38, "Rob Allan" <rob_allan at trimble.com>:
> > I tend to agree with André (not surprising as he largely agreed with
> me!). I'm not so sure about Bo's opinion that there would be lots of pain
> and complaint if the C++ classes provided a rich API to the Qt Quick object
> model. It seems like the object model is becoming more stable, and given
> that PIMPL hides most of the inner workings, it should be possible to
> continue to evolve the API with judicious use of "deprecated" pragmas, etc.
> Of course there will always be some "true" breaking changes that cause
> compile errors for Qt users, but would there really be such an outcry about
> that? Not sure.
> >
> > I quite like QML as a declarative markup language, but am less enthused
> about JavaScript. It seems like kind of a toy programming language. I'm a
> bit shocked that you can write "code" where you can happily call functions
> or access properties that don't even exist on the target object.
>
> Enter OOP. In classic OOP there are no function calls, you just send
> messages to object, and object dispatches them "somehow"
>
> Qt metaobject system has same properties, e.g. you can assign or read
> non-existing properties, connect to missing slots, etc.
>
> >It is so easy to introduce a typo, or to remove a function or property
> that is still needed somewhere else, and not realise it. You won't get a
> compile error, or even a runtime crash, just strange behavior and
> maybe something in the console log. And having functional code spread
> across C++ and JavaScript seems less than ideal. I'm kind of getting used
> it, and trying to do only layout-related stuff in the JavaScript, and
> anything that is more related to application logic in C++. So you can
> certainly make it work - but I still feel you could produce a more robust
> application if all of your coding could be done in C++ and none in
> JavaScript.
>
> Don't you have unit tests?
>
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