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Nearly everything that is mentioned in this blog is a subject of change / addition to the latest C standard, code named C2x. They are in discussions to introdu

Nearly everything that is mentioned in this blog is a subject of change / addition to the latest C standard, code named C2x. They are in discussions to introduce the following in C: * nullptr * auto * __has_include * make false and true first-class language features * constexpr and lots of other goodies [1]. https://gustedt.wordpress.com/2018/11/12/c2x/ https://gustedt.wordpress.com/2018/11/12/c2x/

mehrdadn 7y ago
Are they trying to make C literally become the same as C++ except classes and templates?
- banachtarski 7y ago
  Are classes and templates not the bulwark of what makes C++ C++ though
- stephen82 7y ago
  Well, they are trying to slim down, so to speak, the gap between C and C++ for the sake of a safer interoperability between the languages and for the sake of safer and secure code. If C could fix _Generic from C11 and make it behave more like a lightweight version of templates, then I could say we have a huge potential of having a safer version of what we currently have.
- loeg 7y ago
  > Are they trying to make C literally become the same as C++ except classes and templates? As a C programmer, aren't classes, templates, and exceptions the things that have classically differentiated C and C++?[0] I don't see anything obviously objectionable about nullptr[1], auto, __has_include, or constexpr. (I don't have a ton of experience with them, either.) I'll admit I don't really grok what "make false and true first-class language features" means — maybe make them reserved keywords? (int)true must still evaluate to 1, in any event. [0]: "C++ is C with classes!" [1]: C's "NULL" has this obnoxious wart in that it is implementation-defined whether or not it is a pointer type. I.e., it can be "(void *)0" or just "0". This means that it cannot be used safely in portable incantations of variadic functions that expect pointer arguments.
  - mehrdadn 7y ago
    They're not the "problems" with C++, they're what make C++ great. It's like C is slowly realizing C++ features are actually useful, but doing so as slowly as molasses, while still trying to pretend like this isn't the case...
    - loeg 7y ago
      > [Classes, templates, and exceptions are] not the "problems" with C++, they're what make C++ great. We're going to have to agree to disagree on that one. > It's like C is slowly realizing C++ features are actually useful, but doing so as slowly as molasses, while still trying to pretend like this isn't the case... I think it makes sense to adopt C++ features that do some combination of (1) providing a useful feature, (2) aiding C++ compatibility, and (3) not majorly increasing the conceptual size of the C language. Just like it makes sense for C++ to adopt C99-compatibility (structure literals has taken y'all like 20+ years to adopt). Templates, classes, and exceptions are a huge huge addition to the complexity of the language. If C programmers wanted them, with all of the pitfalls of manual memory management and C-style lifetime safety, they'd just use C++. Obviously, they don't. Personally, if I had to choose a language other than C I'd pick something like Zig, Rust, or Go over C++.
      - de_watcher 7y ago
        C with templates (not classes), STL algorithms/ranges and small things like nullptr, auto, lambdas, stronger basic types, etc is actually a powerful configuration.
        loeg 7y ago
        Everyone who likes C++ will tell you which parts they like and how powerful they are :-).
  - klingonopera 7y ago
    > This means that it cannot be used safely in portable incantations of variadic functions that expect pointer arguments. Why only variadic functions? The answer to that may make my next question obsolete, namely: Wouldn't only C++ complain about this? In C, isn't the input to anything coerced to the data type it will represent, in actual complete disregard of the input type?
- turndown 7y ago
  I do not really care about new features to C - I would just use C++ for these features - but what is your specific argument against something like auto? Or just in general on new features.
glouwbug 7y ago
"Add a type aware print utility with format specification syntax similar to python" Now thats exciting
- czr 7y ago
  does anyone have more information on this? only reference I can find is that blog post; I can't find the specific section of the linked specs that discusses such a utility
- colonwqbang 7y ago
  __attribute__((format(printf, ...))) makes printf every bit as type-aware as I need it to be. Put that in the standard instead.

mehrdadn 7y ago

Are they trying to make C literally become the same as C++ except classes and templates?

banachtarski 7y ago
Are classes and templates not the bulwark of what makes C++ C++ though
stephen82 7y ago
Well, they are trying to slim down, so to speak, the gap between C and C++ for the sake of a safer interoperability between the languages and for the sake of safer and secure code. If C could fix _Generic from C11 and make it behave more like a lightweight version of templates, then I could say we have a huge potential of having a safer version of what we currently have.
loeg 7y ago
> Are they trying to make C literally become the same as C++ except classes and templates? As a C programmer, aren't classes, templates, and exceptions the things that have classically differentiated C and C++?[0] I don't see anything obviously objectionable about nullptr[1], auto, __has_include, or constexpr. (I don't have a ton of experience with them, either.) I'll admit I don't really grok what "make false and true first-class language features" means — maybe make them reserved keywords? (int)true must still evaluate to 1, in any event. [0]: "C++ is C with classes!" [1]: C's "NULL" has this obnoxious wart in that it is implementation-defined whether or not it is a pointer type. I.e., it can be "(void *)0" or just "0". This means that it cannot be used safely in portable incantations of variadic functions that expect pointer arguments.
- mehrdadn 7y ago
  They're not the "problems" with C++, they're what make C++ great. It's like C is slowly realizing C++ features are actually useful, but doing so as slowly as molasses, while still trying to pretend like this isn't the case...
  - loeg 7y ago
    > [Classes, templates, and exceptions are] not the "problems" with C++, they're what make C++ great. We're going to have to agree to disagree on that one. > It's like C is slowly realizing C++ features are actually useful, but doing so as slowly as molasses, while still trying to pretend like this isn't the case... I think it makes sense to adopt C++ features that do some combination of (1) providing a useful feature, (2) aiding C++ compatibility, and (3) not majorly increasing the conceptual size of the C language. Just like it makes sense for C++ to adopt C99-compatibility (structure literals has taken y'all like 20+ years to adopt). Templates, classes, and exceptions are a huge huge addition to the complexity of the language. If C programmers wanted them, with all of the pitfalls of manual memory management and C-style lifetime safety, they'd just use C++. Obviously, they don't. Personally, if I had to choose a language other than C I'd pick something like Zig, Rust, or Go over C++.
    - de_watcher 7y ago
      C with templates (not classes), STL algorithms/ranges and small things like nullptr, auto, lambdas, stronger basic types, etc is actually a powerful configuration.
      - loeg 7y ago
        Everyone who likes C++ will tell you which parts they like and how powerful they are :-).
- klingonopera 7y ago
  > This means that it cannot be used safely in portable incantations of variadic functions that expect pointer arguments. Why only variadic functions? The answer to that may make my next question obsolete, namely: Wouldn't only C++ complain about this? In C, isn't the input to anything coerced to the data type it will represent, in actual complete disregard of the input type?
turndown 7y ago
I do not really care about new features to C - I would just use C++ for these features - but what is your specific argument against something like auto? Or just in general on new features.

glouwbug 7y ago

"Add a type aware print utility with format specification syntax similar to python" Now thats exciting

czr 7y ago
does anyone have more information on this? only reference I can find is that blog post; I can't find the specific section of the linked specs that discusses such a utility
colonwqbang 7y ago
__attribute__((format(printf, ...))) makes printf every bit as type-aware as I need it to be. Put that in the standard instead.