5 ms·

Verity Stob's guide to upcoming C++0x

36 points by ableal 18y ago

ableal 18y ago
Seems they're not quite done nailing legs to C++. I suppose it will run faster, but "easily understandable by anyone with half a dozen brains" is my take. [Confession: I once caused the Bell Labs 'cfront' tape to be ordered, and loaded into unsuspecting Vaxen innocently running BSD Unix, at an otherwise reputable school. I allege, in my defense, that I mostly used it only as "a better C" (back then, C did not have function prototypes); and that, at the time, no other grad students were noticeably (further) deranged by the availability of C++.]
- old-gregg 18y ago
  Well... I'd say C++ even with these latest improvements is much easier to grasp than Haskell, for example. The question is if the steep learning curve can be justified. I'd say that for some it makes sense. Updated C++ will be a fairly high-level language with absolute access to bare metal and near 100% compatibility with C, that's very unique. And the world is in a desperate need for a deterministic (i.e. optionally garbage-collected) bare-metal replacement for C for systems programming. D could be it, but Walter just won't let the community to have some control of it. Moreover, I suspect some of these improvements around the type system will allow C++ compilers to generate faster code than C compiler could ever achieve because programmer's intentions will be better expressed. I only wish they expanded the standard library more. As far as I'm concerned, C++ doesn't really have a standard lib: STL is often awkward to use and very limited, for instance std::string is next to useless and iostream is such a pain... Then we have Boost, it comes with insane build times, incomprehensible compile error messages and multi-platform issues, so most C++ programs mostly fall back to C lib for basics like I/O, or to platform-dependent frameworks like MFC. I also hope that external templates will work as promised. In the current form, templatized C++ works well only in a form of one giant file where everything is included in the correct order. Perhaps this is why every single C++ project in my relatively long C++ career has been using the language in "C with classes" form despite my best attempts to convince people that templates aren't always evil.
  - babo 18y ago
    Haskell is way more consistent for me, it's easier to understand and debug if comparing it to a template heavy C++ code.
  - ableal 18y ago
    True, but it's become a specialist need - like construction machinery and heavy trucks. I wrote some C++ a few years ago (objects, STL, etc.) in a case where it had been chosen mostly out of inertia - Python could have been used with similar performance and less code (and did get used afterwards for other cases). Speaking of Python and C++: possibly some of us would wish to write Python and get C++. Mark Dufour has been persistently plugging away at a Python-to-C++ compiler (and welcomes help): http://shed-skin.blogspot.com/ http://shed-skin.blogspot.com/
    - old-gregg 18y ago
      If you avoid web programming and SQL-heavy enterprise development C++ is very much mainstream and wouldn't call it a specialist need. Actually, the kind of open source projects I enjoy to tinker with [when not at work] is all C/C++: Qt, Webkit, SQLite, various compilers and interpreters, search engines, etc.
      - ableal 18y ago
        Excellent taste in tinkering, but ... ahem ... aren't those a tad on the infrastructure side ? ("Is this the right room for an argument ?", or are you setting a subtle trap ? ;-) I don't doubt that most of the (non-idle, non-phone/TV/etc.) CPU cycles in the world are probably being burned by executing code written in C/C++. But the stuff in my shopping bag probably also did better than 90% of its movement by truck/train/ship. P.S. Mark Dufour's ShedSkin may have you covered for 100x of that 200x speed hit you mentioned in another thread: http://www.hxa.name/minilight/#comparison http://www.hxa.name/minilight/#comparison is instructive (one small case, restricted, etc. Void where prohibited by law).
      - dchest 18y ago
        SQLite is written in C.
jcl 18y ago
I mean, next year will surely be too late for an '0x' standard? Actually the C-plus-plusers point out it could be delayed until 200A, or indeed until 200F. Yick. Arc may be a "hundred-year language", but if the C++ committee delays to 200A, that would make C++ a six-thousand-year language (8202 in decimal).
- TallGuyShort 18y ago
  Who cares about it representing a year - C++0x is a cool name all by itself!
swolchok 18y ago
Perhaps I misread the article, but isn't it unusually heavy on the snark and light on content for HN?
- jcl 18y ago
  It's not a bad overview. The Register is snarky by nature.
- wingo 18y ago
  I enjoy a good C++ snark from time to time.
- gordonguthrie 18y ago
  Umm, Verity Snob is the funniest writer on Technology going. Its supposed to be geek jokes.
e4m 18y ago
I'm not sure why C++ is the butt of so many jokes. Making fun of it just seems to be the in thing to do. I bet most of the jokers have never seriously used it. Personally, I get a lot of use out of C++ and actually enjoy using it. Sure, it can get complex at times when doing really hard stuff, but it'll force you to stop and understand the implications of what it is you are doing thus forcing you to do it correctly. C++ won't let you get away with half the crap that many other languages will. Knowing C++ will make you a better programmer in all languages. Try it and see.
- windsurfer 18y ago
  I like C++, and I don't like my languages forcing anything on me, unless I tell it to. That's why C++ and perl are among my favourites.
- old-gregg 18y ago
  In this context, first time ever since I joined HN, I'll be brave to openly say this out loud: C++ is my favorite language. Ughh... I did it! :) A little background: I started coding in x86 ASM (because some idiot told me that was the only language computers understood when I was 14), switched to Pascal, then C, then C++, then I got my 1st job as VB6 oracle-to-form data pusher, then I did 5 years of very exciting C++ library development, i.e. other programmers were my customers. [highly recommend this - much easier to market&sell than any other market, learn from DHH, Trolltech or MySQL AB] In 2002 I moved to higher level languages: Python, some Perl and lots of Ruby and Javascript. And honestly I'm not that more productive coding Ruby than I was ever in C++. Yeah, it's nice to read an entire file, break it down into an array of lines, grep them with some regexp and apply a function on each result - all that in a single line of code, but... well, read on: C++ allows for some beautiful type-safe and performant high-level design constructs that Java, Python or even Ruby can't touch: just combine multiple inheritance with medium-complexity templates and see what you can do. Only Haskell gives me the same type-safe, nearly as fast and flexible (yet very high level) material to build software of. Being a realist, I don't see Haskell ever "making it" into the industry, but the updated C++ definitely will. Duck typed languages are nice, but require enormous layers of unit tests to protect yourself from stupid things like misspelled variable names or even renamed/missing code files. Building with Rails without unit testing is a suicide. Doing Haskell without unit testing is actually isn't that bad. And this requirement to test the shit out of your code [2-to-1 ratios aren't uncommon] kills the spirit of exploratory programming for me. Moreover, 200x speed penalty means that simple O(n) algorithms won't cut it for an average data set, forcing you to build more complex solutions just because your language can't scan a big-ass array under 10ms. Moreover, most high-level languages live inside of a VM, which makes them useless for general purpose software development: they represent "fuck you" approach, i.e. they'll easily call your C library, but won't let you easily call them. JAR is as good to me as my swap file: I can't afford to carry around JVM on my back just because I want to call your Java code from Haskell or C++.
jcromartie 18y ago
C++0A... I love it.
abrahamsen 18y ago
The learning curve will be less steep with the new standard, even if the hill is taller. Much of the work on the new standard is focused on making libraries easier to use, including giving better error messages. This will facilitate the "Accelerated C++" approach, namely teaching the libraries first, and the base language later. The other side of this is that it will likely also widen the gap between those who use C++ libraries, and those who write them.
- gchpaco 18y ago
  I have grave difficulties believing this, precisely because in the name of backward compatibility they haven't removed any of the nonsense that made C++ so difficult to wrap one's brain around. Instead, they added even more. None of the corner cases that make C++ so hard to parse have actually been removed, so tools are still hard to write and unreliable. Nothing has been done to allow a user to express where pointer aliasing can occur and, more importantly, where it cannot, so many forms of important numeric optimizations are still extremely difficult. There are still at least three languages possibly intermingled at any given time--macros, template computation (a la Boost), and regular C++, each with its own style of assertion now. Rather than relaxing a restriction on type ordering they invented a whole new function syntax. Managing the variable closure around upward funargs (returning a lambda) is the programmer's responsibility, with a subtle stack smash if you get it wrong, or if anything you call with a lambda stores it somewhere behind your back. Two types of characters aren't enough; now char, char16_t, char32_t, and wchar_t all coexist. You can now create a const char string two ways, one of which is UTF-8 encoded and one of which is encoded any damned way the compiler writer pleases. The raw string syntax, another invention, further complicates the lexer. Objects now silently need a move constructor in certain circumstances to avoid silent, behind the scenes copies. You can't even reliably say "x = y;" any more; operator = can be deleted from whatever type x is. Rather than put the onus on the (admittedly horribly overworked, due to the previous crap) compiler writers to constant fold, now we have constexpr, just like const except different! This is not a programming language. This is a train wreck. Supposedly this language is "close to the metal" but even the simplest operations can perform unbounded amounts of work behind your back (for example, due to implicit conversions, or operator overloading). This language is consumed with a focus on the irrelevant. The Reg article, while very snarky, is not an unreasonable position to be taking here.
Bjoern 18y ago
For all you C++ fans out there, you will find this enlightening. http://www.jwz.org/doc/worse-is-better.html http://www.jwz.org/doc/worse-is-better.html

36 points by ableal 18y ago

Seems they're not quite done nailing legs to C++. I suppose it will run faster, but "easily understandable by anyone with half a dozen brains" is my take. [Confession: I once caused the Bell Labs 'cfront' tape to be ordered, and loaded into unsuspecting Vaxen innocently running BSD Unix, at an otherwise reputable school. I allege, in my defense, that I mostly used it only as "a better C" (back then, C did not have function prototypes); and that, at the time, no other grad students were noticeably (further) deranged by the availability of C++.]

old-gregg 18y ago
Well... I'd say C++ even with these latest improvements is much easier to grasp than Haskell, for example. The question is if the steep learning curve can be justified. I'd say that for some it makes sense. Updated C++ will be a fairly high-level language with absolute access to bare metal and near 100% compatibility with C, that's very unique. And the world is in a desperate need for a deterministic (i.e. optionally garbage-collected) bare-metal replacement for C for systems programming. D could be it, but Walter just won't let the community to have some control of it. Moreover, I suspect some of these improvements around the type system will allow C++ compilers to generate faster code than C compiler could ever achieve because programmer's intentions will be better expressed. I only wish they expanded the standard library more. As far as I'm concerned, C++ doesn't really have a standard lib: STL is often awkward to use and very limited, for instance std::string is next to useless and iostream is such a pain... Then we have Boost, it comes with insane build times, incomprehensible compile error messages and multi-platform issues, so most C++ programs mostly fall back to C lib for basics like I/O, or to platform-dependent frameworks like MFC. I also hope that external templates will work as promised. In the current form, templatized C++ works well only in a form of one giant file where everything is included in the correct order. Perhaps this is why every single C++ project in my relatively long C++ career has been using the language in "C with classes" form despite my best attempts to convince people that templates aren't always evil.
- babo 18y ago
  Haskell is way more consistent for me, it's easier to understand and debug if comparing it to a template heavy C++ code.
- ableal 18y ago
  True, but it's become a specialist need - like construction machinery and heavy trucks. I wrote some C++ a few years ago (objects, STL, etc.) in a case where it had been chosen mostly out of inertia - Python could have been used with similar performance and less code (and did get used afterwards for other cases). Speaking of Python and C++: possibly some of us would wish to write Python and get C++. Mark Dufour has been persistently plugging away at a Python-to-C++ compiler (and welcomes help): http://shed-skin.blogspot.com/ http://shed-skin.blogspot.com/
  - old-gregg 18y ago
    If you avoid web programming and SQL-heavy enterprise development C++ is very much mainstream and wouldn't call it a specialist need. Actually, the kind of open source projects I enjoy to tinker with [when not at work] is all C/C++: Qt, Webkit, SQLite, various compilers and interpreters, search engines, etc.
    - ableal 18y ago
      Excellent taste in tinkering, but ... ahem ... aren't those a tad on the infrastructure side ? ("Is this the right room for an argument ?", or are you setting a subtle trap ? ;-) I don't doubt that most of the (non-idle, non-phone/TV/etc.) CPU cycles in the world are probably being burned by executing code written in C/C++. But the stuff in my shopping bag probably also did better than 90% of its movement by truck/train/ship. P.S. Mark Dufour's ShedSkin may have you covered for 100x of that 200x speed hit you mentioned in another thread: http://www.hxa.name/minilight/#comparison http://www.hxa.name/minilight/#comparison is instructive (one small case, restricted, etc. Void where prohibited by law).
    - dchest 18y ago
      SQLite is written in C.

jcl 18y ago

I mean, next year will surely be too late for an '0x' standard? Actually the C-plus-plusers point out it could be delayed until 200A, or indeed until 200F. Yick. Arc may be a "hundred-year language", but if the C++ committee delays to 200A, that would make C++ a six-thousand-year language (8202 in decimal).

TallGuyShort 18y ago
Who cares about it representing a year - C++0x is a cool name all by itself!

swolchok 18y ago

Perhaps I misread the article, but isn't it unusually heavy on the snark and light on content for HN?

jcl 18y ago
It's not a bad overview. The Register is snarky by nature.
wingo 18y ago
I enjoy a good C++ snark from time to time.
gordonguthrie 18y ago
Umm, Verity Snob is the funniest writer on Technology going. Its supposed to be geek jokes.

e4m 18y ago

I'm not sure why C++ is the butt of so many jokes. Making fun of it just seems to be the in thing to do. I bet most of the jokers have never seriously used it. Personally, I get a lot of use out of C++ and actually enjoy using it. Sure, it can get complex at times when doing really hard stuff, but it'll force you to stop and understand the implications of what it is you are doing thus forcing you to do it correctly. C++ won't let you get away with half the crap that many other languages will. Knowing C++ will make you a better programmer in all languages. Try it and see.

windsurfer 18y ago
I like C++, and I don't like my languages forcing anything on me, unless I tell it to. That's why C++ and perl are among my favourites.
old-gregg 18y ago
In this context, first time ever since I joined HN, I'll be brave to openly say this out loud: C++ is my favorite language. Ughh... I did it! :) A little background: I started coding in x86 ASM (because some idiot told me that was the only language computers understood when I was 14), switched to Pascal, then C, then C++, then I got my 1st job as VB6 oracle-to-form data pusher, then I did 5 years of very exciting C++ library development, i.e. other programmers were my customers. [highly recommend this - much easier to market&sell than any other market, learn from DHH, Trolltech or MySQL AB] In 2002 I moved to higher level languages: Python, some Perl and lots of Ruby and Javascript. And honestly I'm not that more productive coding Ruby than I was ever in C++. Yeah, it's nice to read an entire file, break it down into an array of lines, grep them with some regexp and apply a function on each result - all that in a single line of code, but... well, read on: C++ allows for some beautiful type-safe and performant high-level design constructs that Java, Python or even Ruby can't touch: just combine multiple inheritance with medium-complexity templates and see what you can do. Only Haskell gives me the same type-safe, nearly as fast and flexible (yet very high level) material to build software of. Being a realist, I don't see Haskell ever "making it" into the industry, but the updated C++ definitely will. Duck typed languages are nice, but require enormous layers of unit tests to protect yourself from stupid things like misspelled variable names or even renamed/missing code files. Building with Rails without unit testing is a suicide. Doing Haskell without unit testing is actually isn't that bad. And this requirement to test the shit out of your code [2-to-1 ratios aren't uncommon] kills the spirit of exploratory programming for me. Moreover, 200x speed penalty means that simple O(n) algorithms won't cut it for an average data set, forcing you to build more complex solutions just because your language can't scan a big-ass array under 10ms. Moreover, most high-level languages live inside of a VM, which makes them useless for general purpose software development: they represent "fuck you" approach, i.e. they'll easily call your C library, but won't let you easily call them. JAR is as good to me as my swap file: I can't afford to carry around JVM on my back just because I want to call your Java code from Haskell or C++.

jcromartie 18y ago

C++0A... I love it.

abrahamsen 18y ago

The learning curve will be less steep with the new standard, even if the hill is taller. Much of the work on the new standard is focused on making libraries easier to use, including giving better error messages. This will facilitate the "Accelerated C++" approach, namely teaching the libraries first, and the base language later. The other side of this is that it will likely also widen the gap between those who use C++ libraries, and those who write them.

gchpaco 18y ago
I have grave difficulties believing this, precisely because in the name of backward compatibility they haven't removed any of the nonsense that made C++ so difficult to wrap one's brain around. Instead, they added even more. None of the corner cases that make C++ so hard to parse have actually been removed, so tools are still hard to write and unreliable. Nothing has been done to allow a user to express where pointer aliasing can occur and, more importantly, where it cannot, so many forms of important numeric optimizations are still extremely difficult. There are still at least three languages possibly intermingled at any given time--macros, template computation (a la Boost), and regular C++, each with its own style of assertion now. Rather than relaxing a restriction on type ordering they invented a whole new function syntax. Managing the variable closure around upward funargs (returning a lambda) is the programmer's responsibility, with a subtle stack smash if you get it wrong, or if anything you call with a lambda stores it somewhere behind your back. Two types of characters aren't enough; now char, char16_t, char32_t, and wchar_t all coexist. You can now create a const char string two ways, one of which is UTF-8 encoded and one of which is encoded any damned way the compiler writer pleases. The raw string syntax, another invention, further complicates the lexer. Objects now silently need a move constructor in certain circumstances to avoid silent, behind the scenes copies. You can't even reliably say "x = y;" any more; operator = can be deleted from whatever type x is. Rather than put the onus on the (admittedly horribly overworked, due to the previous crap) compiler writers to constant fold, now we have constexpr, just like const except different! This is not a programming language. This is a train wreck. Supposedly this language is "close to the metal" but even the simplest operations can perform unbounded amounts of work behind your back (for example, due to implicit conversions, or operator overloading). This language is consumed with a focus on the irrelevant. The Reg article, while very snarky, is not an unreasonable position to be taking here.

Bjoern 18y ago

For all you C++ fans out there, you will find this enlightening. http://www.jwz.org/doc/worse-is-better.html http://www.jwz.org/doc/worse-is-better.html