[Qt-interest] Advices on safer SIGNAL macro

[Thiago Macieira]

On Wednesday, 19 de October de 2011 21:47:18 Johannes Schaub wrote:
> namespace static_signal_detail {
>    template<typename>
>    struct take { };
> }
> 
> #define STATIC_SIGNAL(SIG) (static_signal_detail::take<void(void SIG)>(), \
>                             SIGNAL(SIG))

It's an interesting technique. It will verify that the types exist. However, 
it will not complain about:

	connect(this, SIGNAL(changed(int id)), SLOT(executeAction()));

The compiler will find nothing wrong with the presence of the name of the 
parameter, but QObject::connect will.

It will also not complain in your case:

>    connect(pages, SIGNAL(changed(Ptr)), SLOT(update(Ptr)));

If Ptr is a local type.

The Qt 5 solution is more powerful and will check all cases.

-- 
Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
   Software Architect - Intel Open Source Technology Center
      PGP/GPG: 0x6EF45358; fingerprint:
      E067 918B B660 DBD1 105C  966C 33F5 F005 6EF4 5358
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 190 bytes
Desc: This is a digitally signed message part.
Url : http://lists.qt-project.org/pipermail/qt-interest-old/attachments/20111019/a170ddc8/attachment.bin