Re: __event?

From:

"Ben Voigt [C++ MVP]" <rbv@nospam.nospam>

Newsgroups:

microsoft.public.dotnet.languages.vc,microsoft.public.vc.language

Date:

Fri, 31 Aug 2007 14:55:45 -0500

Message-ID:

<0D7080F8-D5D6-4499-907E-0C81646854BF@microsoft.com>

"PGP" <priyesh_do_not_reply> wrote in message
news:ugcVcU$6HHA.3900@TK2MSFTNGP02.phx.gbl...

"Ben Voigt [C++ MVP]" <rbv@nospam.nospam> wrote in message
news:%23TMSekz6HHA.5212@TK2MSFTNGP04.phx.gbl...

"PGP" <priyesh_do_not_reply> wrote in message
news:uhjxRTy6HHA.3740@TK2MSFTNGP02.phx.gbl...

Anybody here using __event? Could you please discuss any potential
issues with it other than portability?

Nope. People using C++ in the managed world are now using C++/CLI (new
in VC++ 2005) which no longer supports the __event keyword, instead using
"context-sensitive" keywords that are only recognized at certain
locations.

I was wondering about the native C++ part of it. Would you rather look
into

You were in the C++/CLI newsgroup... microsoft.public.vc.language is focused
on native features.

a third party library or would you consider using the __event, __hook
and __unhook? Overall, I did not find any good feedback on the __event
mechanism during my research, but I would defenitely want to use it
if it's here to stay. I have done some tests of my own and tried out
MSDN samples. It does exactly what I want it to do. Now I am
looking for some reassurance.

Are you looking for COM compatibility? If you just want event handling in
within a C++ application, then pointer-to-member-function is 100% in the C++
standard and does what you want. In the rare case you need to support
multiple subscribers, then a std::vector or std::list of
pointer-to-member-function will get you there, again 100% standard and
portable. A template helper function can hide the details of iterating
through and calling all receivers. That will get even better in C++0x with
template support for arbitrary argument lists (not sure what the correct
name of the feature is).

Priyesh