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Mon, 12 October 2020 22:31

Klugier
Messages: 1099
Registered: September 2012
Location: Poland, Kraków

Senior Contributor

Hello,

I had the discussion with Mirek about this article https://evileg.com/en/post/629/ he found that the user uses deprecated THISBACK construction. Well we deprecated it in the documentation in favor or lambdas or newer c++ constructions such as Function, Gate etc.

In c++14 which we targets on all platforms the solution is easy. We can deprecate it on compilation level, which means something. Just mark THISBACK with deprecated atribute like this:

[[deprecated("THISBACK is deprecated use lambda instead.")]]
const int thisbackd = 0;

#define THISBACK(x)                  callback(this  + thisbackd, &CLASSNAME::x)
#define THISBACK1(x, arg)            callback1(this + thisbackd, &CLASSNAME::x, arg)
#define THISBACK2(m, a, b)           callback2(this + thisbackd, &CLASSNAME::m, a, b)
#define THISBACK3(m, a, b, c)        callback3(this + thisbackd, &CLASSNAME::m, a, b, c)
#define THISBACK4(m, a, b, c, d)     callback4(this + thisbackd, &CLASSNAME::m, a, b, c, d)
#define THISBACK5(m, a, b, c, d, e)  callback5(this + thisbackd, &CLASSNAME::m, a, b, c, d,e)

Then in all places when THISBACK is used the warning pop up "/home/klugier/upp/uppsrc/CtrlLib/FileSel.h (239): warning: 'thisbackd' is deprecated: THISBACK is deprecated use lambda instead. [-Wdeprecated-declarations]".

If you are not aware how you should replace thisback. Example below:

void MyWidnow::ErrorMenu(Bar& bar)
    // bar.Add("Copy all", THISBACK1(CopyError, true));
    bar.Add("Copy all", [=] { CopyError(true); });

    // In the header file no need for "typedef MyWindow CLASSNAME" declaration...

I think we have multiple places when [[deprecated]] macro can be used. If you search for "deprecated" in uppsrc then there is around 52 entries... Definitely not the topic for 2020.2, but for 2021.1...

Klugier

U++ - one framework to rule them all.

[Updated on: Tue, 13 October 2020 11:29]

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