3 ms·

It's amazing how many people try to write generic containers for C, when there is already a perfect solution for that, called C++. It's impossible to write gene

It's amazing how many people try to write generic containers for C, when there is already a perfect solution for that, called C++. It's impossible to write generic type-safe code in C, and this version resorts to using GCC extensions to the language (note the ({…}) expressions). For those afraid of C++: you don't have to use all of it at once, and compilers have been great for the last few decades. You can easily port C code to C++ (often you don't have to do anything at all). Just try it out and reassess the objections you have.

serbuvlad 1y ago
My problem with C++, and maybe this is just me, is RAII. Now, Resource Aquisition Is Initialization is correct, but the corollary is not generally true, which is to say, my variable going out of scope does not generally mean I want to de-aquire that resource. So, sooner or later, everything gets wrapped in a reference counting smart pointer. And reference counting always seemed to me to be a primitive or last-resort memory managment strategy.
- secondcoming 1y ago
  If you want to take back manual control, use the release() function
- gpderetta 1y ago
  Your problem is not with RAII, but with reference counting, which you correctly identified should be the last resort, not the default; at least for the applications typically written in C++.
  - Levitating 1y ago
    Why should reference counting be a last resort?
    - rurban 1y ago
      Because it's insanely slow, and doesn't support cyclic structures.
    - gpderetta 1y ago
      ... in C++. Because, at least in C++, it is a bad, slow and inconvenient GC. If you want or need generalized GC there are significantly better languages for that.
- spacechild1 1y ago
  > my variable going out of scope does not generally mean I want to de-aquire that resource. But it does! When an object goes out of scope, nobody can/shall use it anymore, so of course it should release its (remaining) resources. If you want to hold on the object, you need to revisit its lifetime and ownership, but that's independent from RAII.
- Lvl999Noob 1y ago
  Instead of reference counting, consider having two types. An "owner" type which actually contains the resource and the destructor to dequire the resource. And "lender" types which contain a reference (a pointer or just logically (e.g., an fd can just be copied into the lender but only closed by the owner) to the resource which don't dequire on destruction. Same thing as what Rust does with `String` and `str`.
uecker 1y ago
Except that I find C++ far from being perfect. In fact, I switched from C++ to C (a while ago) to avoid its issues and I am being much happier I also find my vec(int) much nicer. In fact, we are at the moment ripping out some template code in a C code base which has some C++ for cuda in it, and this one file with C++ templates almost doubles the compilation time of the complete project (with ~700 source files). IMHO it is grotesque how bad it is.

serbuvlad 1y ago

My problem with C++, and maybe this is just me, is RAII. Now, Resource Aquisition Is Initialization is correct, but the corollary is not generally true, which is to say, my variable going out of scope does not generally mean I want to de-aquire that resource. So, sooner or later, everything gets wrapped in a reference counting smart pointer. And reference counting always seemed to me to be a primitive or last-resort memory managment strategy.

secondcoming 1y ago
If you want to take back manual control, use the release() function
gpderetta 1y ago
Your problem is not with RAII, but with reference counting, which you correctly identified should be the last resort, not the default; at least for the applications typically written in C++.
- Levitating 1y ago
  Why should reference counting be a last resort?
  - rurban 1y ago
    Because it's insanely slow, and doesn't support cyclic structures.
  - gpderetta 1y ago
    ... in C++. Because, at least in C++, it is a bad, slow and inconvenient GC. If you want or need generalized GC there are significantly better languages for that.
spacechild1 1y ago
> my variable going out of scope does not generally mean I want to de-aquire that resource. But it does! When an object goes out of scope, nobody can/shall use it anymore, so of course it should release its (remaining) resources. If you want to hold on the object, you need to revisit its lifetime and ownership, but that's independent from RAII.
Lvl999Noob 1y ago
Instead of reference counting, consider having two types. An "owner" type which actually contains the resource and the destructor to dequire the resource. And "lender" types which contain a reference (a pointer or just logically (e.g., an fd can just be copied into the lender but only closed by the owner) to the resource which don't dequire on destruction. Same thing as what Rust does with `String` and `str`.

uecker 1y ago

Except that I find C++ far from being perfect. In fact, I switched from C++ to C (a while ago) to avoid its issues and I am being much happier I also find my vec(int) much nicer. In fact, we are at the moment ripping out some template code in a C code base which has some C++ for cuda in it, and this one file with C++ templates almost doubles the compilation time of the complete project (with ~700 source files). IMHO it is grotesque how bad it is.