Stroustrup Says New C++ Standard Delayed Until 2010 Or Later

wandazulu writes "At the end of an article written by the creator of C++, where he talks about removing a feature from the new C++ standard, he drops a bombshell: The new C++ standard (typically referred to as C++0x) has been delayed until 2010 or later. What does this mean? No new C++ features like threads, proper enum classes, or hash tables. C++0x is dead, long live C++1x!"

Comments

But will they be useful without concepts?

[wowbagger]

"Do you really want to hold back all the other very important features like lambda, rvalue references, variadic templates, type deduction etc. just because of concepts?"

Unfortunately, without concepts, many of the templates that would make features like those REALLY powerful aren't implementable due to silly things like the compiler insisting upon being able to instantiate member functions that don't make sense for a class and won't be used, just because there isn't a means to tell the compiler "and if this member doesn't make sense, just don't instantiate it, and throw an error IF AND ONLY IF somebody tries to use it." (and yes, I know about SFINAE, but that gets REALLY UGLY to do).

I've been bit by this, where I ended up having to create two completely separate template classes, one for objects that don't have sub-members and one for objects that do, just because I couldn't tell the compiler "Look, if operator . doesn't exist for this method, then don't worry about it!"

That said: I will say, I felt that some of the implementation details of concepts felt "forced" to me, in the same way that the streams library feels "forced": they "hacked" (in the bad way) the library in using language semantics that weren't a good fit.

<sigh/> - I hope the extra time will allow them to put a bit more polish on how you actually express things, and make it feel less "forced"....

Re:So in reality we shouldn't use it until 2015 th

[shutdown -p now]

I've been following C++0x for a long time now, and have been looking forward to it, but now I'm not so sure I'll ever use it. I was looking forward to Concepts more than anything and with that gone, it seems like a extremely minor upgrade.

I would disagree on this part. I'm already using some C++0x features actively in production code, and I can say that they are well worth it. Lambdas are extremely handy as they finally let you use STL (and Boost) algorithms properly without lots of unneeded hand-waving. This may sound a minor thing, but remember how things have changed in C# world when anonymous delegates were introduced in C# 2.0, and their syntax simplified in 3.0? All of a sudden, everyone shifted to functional ("LINQ") techniques of writing code, abandoning hand-coded loops. The same thing happens here.

The second big part is rvalue references. They really do give major performance benefits for STL containers, especially of user-defined types (as smart implementations of C++03 already optimize their containers for standard types to avoid copy by using swap instead - but they can only legally do it for types they control...).

One other thing. C++0x may take a while to be released, but you'll see quite a few of its features in production-quality compilers before the spec is finalized. I've already pointed out that some are in VC++2010. There's even more in newer g++ versions (IIRC, they implement all that stuff, and also variadic templates). I've also seen mention of rvalue references and lambdas in the feature list of the most recent C++Builder release. All in all, this means that you'll have them at your disposal within a year or so one way or another.

Re:How about a REAL C++ feature....

[Joce640k]

That's funny cause I've never seen a single C# or Java app.

 

Where are they? If C# and Java are so great, where are the apps? It's been, what, twelve years since it was announced that they'd take over the world and make C and C++ obsolete but I've yet to see a C# or Java program that wasn't some simple sort of utility or the GUI layer over a C++ app (eg Norton products).

 

What I have noticed is that all those "GUI layer over a C++ app" programs are enormous. 200Mb for a disk backup program (both Norton Ghost and Acronis TrueImage went from 20Mb to 300Mb during their transition-from-C phase and neither of them seems any better off for it.

 

Firefox memory usage is a mystery to me. I can't conceive of how it uses so much memory just to show a few pages of text with embedded images. The other browsers aren't really far behind though so maybe I'm missing something.

Re:And nothing of value was lost

[Stele]

I think bigger problems are C++'s complexity, the presence of pointers, the use of include files, and the lack of garbage collection.

Funny - I see all of those things as advantages.

Re:How about a REAL C++ feature....

[squoozer]

Back in the day they used to have little children crawling around under cotton stipping machines. The children were needed to pick up fluff and other debris that would cause the machine to break the thread it was working on. Some children would get crushed in the machine because they weren't fast enough to get out of the way etc.

C++ is a bit like that machine. It works fine if you have the luxury of being able to pick only the fastest most able children but there comes a time when you need to grow your business beyond the limits of what the best can achieve. At that point you need to either accept that some of the less able children will get crushed (bugs in the code) or you need to make the machine safer. It's often cheaper and simpler to make the machine safer and hopefully those most able children will then be able to perform more complex and hopefully profitable work.

To paraphrase... everytime you argue for a language without safety features god kills a child.