The ISO C++ committee met in Berlin from April 2-7, 2006. I thought I'd write a quick note about highlights of what was decided for C++0x:

 

 

First, how to find out for yourself: The minutes of each meeting are usually available online about 2-3 weeks after the meeting. The easiest way to find WG21 minutes for a given meeting/year is to Google for "wg21 <year> minutes," in this case "wg21 2006 minutes." One of the first results is:

 

  Minutes of J16 Meeting No. 42/WG21 Meeting No. 37, April 3-7, 2006
  http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2006/n1993.html

 

BTW, in general, the easiest way to find any WG21 doc is to Google for "wg21 <doc number>". That's what I always do, because it's quicker than navigating my own hard drive even though I know where the doc is.

 

 

 

At this meeting, five major pieces of work got approved into the draft. That means these features can (and likely will) still get tweaked and changed until the standard is actually finalized and published, but the upshot of being voted into the working paper is that these features are "for real" -- they've been discussed and debated, consensus has been achieved on their specification, actual wording written up in standardese, and a full committee vote passed to stick the standardese into the working paper.

 

The only part that wasn't voted in was the special mathematical functions, which are of interest principally only to heavy-duty scientists and mathematicians. The actual TR is in the process of publication, but you can find a nearly-final version on the ISO C++ committee website here: N1836, Draft Technical Report on C++ Library Extensions.

 

This permits you to write declarations like

 

 

where the type is deduced from the initializer. So in this case, x has type double, and i has type map<string,unordered_map<int,tupe<float,string,const int> > >::const_iterator or whatever the right type happens to be, without having to spell it out. The paper is: N1984, Deducing the type of variable from its initializer expression (revision 4).

 

This proposal was written by me and Francis Glassborow. It's a combined WG21 / C++/CLI proposal, though it was cut from the first edition of C++/CLI; if C++/CLI does add this it will follow this that WG21 has adopted (plus any future tweaks). The paper is: N1986, Delegating Constructors (revision 3).

 

This fixes a tiny but perniciously annoying and embarrassing quirk of C++, and the fix adopted by C++ is the same that C++/CLI specified. Right angle brackets have been fixed so that constructions Like<This<Nested<Template>>>> will work sensibly, without having to write the closing right angle brackets with extra whitespace Like<You<Must<Today>  >  >  > which is annoying, embarrassing, and suspected of contributing to dental decay among 18- to 24-year-olds in northeastern Mississippi. To find out more, see the paper: N1757, Right Angle Brackets (Revision 2).

 

The terse paper is: N1987, Adding 'extern template' (version 2).

 

Enjoy! And there's more to come when we meet next, in October 2006 (Portland, OR, USA).

 

Herb