4 ms·

They don't solve problems created by C, they just solve problems C doesn't. The problems still exist, and sometimes the high-level compiler even picks the wrong

They don't solve problems created by C, they just solve problems C doesn't. The problems still exist, and sometimes the high-level compiler even picks the wrong solution. Learning C helps you understand when and why this has happened.

flyinglizard 8y ago
Arguably those problems did not exist before the C-era as software wasn't large or complicated enough. C++ directly attempts to improve over C by providing new mechanisms to solve problems encountered by C developers every day. Point is that out of context, a lot of the things modern languages provide seem superfluous. Why have objects? Why have templates, closures, or lambdas? For a novice programmer, these are many answers for questions yet to be asked. When you come from a heavy C background and you encounter something like templates, you know EXACTLY what this is for and wish you had it years ago. I'm as hardcore as they get C programmer and I'm having a ball with C# for this very reason.
- Sir_Cmpwn 8y ago
  When I see templates, I run in the opposite direction at a dead sprint. C++ has added very little of value to the language and templates are one of their worst offerings. Metaprogramming is an antipattern in C.
  - sevensor 8y ago
    > Metaprogramming is an antipattern in C. Yet we often see passionate arguments in its favor, as for instance from Sústrik (http://250bpm.com/blog:56 http://250bpm.com/blog:56) and Tatham (https://www.chiark.greenend.org.uk/~sgtatham/mp/ https://www.chiark.greenend.org.uk/~sgtatham/mp/) and a person on the internet who recommends replacing LAPACK with preprocessor macros (http://wordsandbuttons.online/outperforming_lapack_with_c_metaprogramming.html http://wordsandbuttons.online/outperforming_lapack_with_c_me...). Would you care to comment on its enduring popularity?
    - Sir_Cmpwn 8y ago
      You can write bad code in any language, C is no exception. We also see people persistently arguing in favor of simpler and less magical C. If you want reliable, maintainable code in any language, do not use magic. Metaprogramming is cool, no doubt about it, but it's unnecessary and creates bad code.
lmm 8y ago
"Exploding" undefined behaviour is a problem created by C. Other languages don't have it, not even assembly languages.
- steveklabnik 8y ago
  There are many languages which have undefined behavior. C does have a lot of it, and it can be anywhere. In many languages, you can cause undefined behavior through its FFI. Some languages, like Rust, have UB, but only in well-defined places (a module containing unsafe code, in its case).
  - lmm 8y ago
    If a language lets you cause undefined behaviour via FFI into C, I think it's fair to say that that remains a problem created by C. I do take your point about Rust, but I'd see that as deriving from LLVM's undefined behaviour which in turn descends from C; I'm not aware of any pre-C languages having C-style exploding undefined behaviour or of any subsequent languages inventing it independently.
    - steveklabnik 8y ago
      > I think it's fair to say that that remains a problem created by C. That is fair, however, I don't think it's inherently due to C. Yes, most languages use the C ABI for FFI, but that doesn't mean they have to; it's a more general problem when combining two systems, they cannot track statically the guarantees of the other system. With Rust, it has nothing to do with LLVM; it has to do with the fact that we cannot track things, that's why it's unsafe! Even if an implementation of the language does not use LLVM, we will still have UB.
      - lmm 8y ago
        > With Rust, it has nothing to do with LLVM; it has to do with the fact that we cannot track things, that's why it's unsafe! Even if an implementation of the language does not use LLVM, we will still have UB. I can see that any implementation of unsafe Rust would always have assembly-like unsafeness (e.g. reading an arbitrary memory address might result in an arbitrary value, or segfault). But I don't see why you would need C-style "arbitrary lines before and after the line that will not execute, reads from unrelated memory addresses will return arbitrary values" UB?

flyinglizard 8y ago

Arguably those problems did not exist before the C-era as software wasn't large or complicated enough. C++ directly attempts to improve over C by providing new mechanisms to solve problems encountered by C developers every day. Point is that out of context, a lot of the things modern languages provide seem superfluous. Why have objects? Why have templates, closures, or lambdas? For a novice programmer, these are many answers for questions yet to be asked. When you come from a heavy C background and you encounter something like templates, you know EXACTLY what this is for and wish you had it years ago. I'm as hardcore as they get C programmer and I'm having a ball with C# for this very reason.

Sir_Cmpwn 8y ago
When I see templates, I run in the opposite direction at a dead sprint. C++ has added very little of value to the language and templates are one of their worst offerings. Metaprogramming is an antipattern in C.
- sevensor 8y ago
  > Metaprogramming is an antipattern in C. Yet we often see passionate arguments in its favor, as for instance from Sústrik (http://250bpm.com/blog:56 http://250bpm.com/blog:56) and Tatham (https://www.chiark.greenend.org.uk/~sgtatham/mp/ https://www.chiark.greenend.org.uk/~sgtatham/mp/) and a person on the internet who recommends replacing LAPACK with preprocessor macros (http://wordsandbuttons.online/outperforming_lapack_with_c_metaprogramming.html http://wordsandbuttons.online/outperforming_lapack_with_c_me...). Would you care to comment on its enduring popularity?
  - Sir_Cmpwn 8y ago
    You can write bad code in any language, C is no exception. We also see people persistently arguing in favor of simpler and less magical C. If you want reliable, maintainable code in any language, do not use magic. Metaprogramming is cool, no doubt about it, but it's unnecessary and creates bad code.

lmm 8y ago

"Exploding" undefined behaviour is a problem created by C. Other languages don't have it, not even assembly languages.

steveklabnik 8y ago
There are many languages which have undefined behavior. C does have a lot of it, and it can be anywhere. In many languages, you can cause undefined behavior through its FFI. Some languages, like Rust, have UB, but only in well-defined places (a module containing unsafe code, in its case).
- lmm 8y ago
  If a language lets you cause undefined behaviour via FFI into C, I think it's fair to say that that remains a problem created by C. I do take your point about Rust, but I'd see that as deriving from LLVM's undefined behaviour which in turn descends from C; I'm not aware of any pre-C languages having C-style exploding undefined behaviour or of any subsequent languages inventing it independently.
  - steveklabnik 8y ago
    > I think it's fair to say that that remains a problem created by C. That is fair, however, I don't think it's inherently due to C. Yes, most languages use the C ABI for FFI, but that doesn't mean they have to; it's a more general problem when combining two systems, they cannot track statically the guarantees of the other system. With Rust, it has nothing to do with LLVM; it has to do with the fact that we cannot track things, that's why it's unsafe! Even if an implementation of the language does not use LLVM, we will still have UB.
    - lmm 8y ago
      > With Rust, it has nothing to do with LLVM; it has to do with the fact that we cannot track things, that's why it's unsafe! Even if an implementation of the language does not use LLVM, we will still have UB. I can see that any implementation of unsafe Rust would always have assembly-like unsafeness (e.g. reading an arbitrary memory address might result in an arbitrary value, or segfault). But I don't see why you would need C-style "arbitrary lines before and after the line that will not execute, reads from unrelated memory addresses will return arbitrary values" UB?