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Comment by VorpalWay | Hacker News Reader

Yes that is annoying, but I don't know of any mainstream systems language that does. C and C++ can also have allocations anywhere, and C++ have exceptions. And those are really the only competitors to Rust for what I do (hard realtime embedded).

Zig might be an option in the future, and it does give more control over allocations. I don't know what the exception story is there, and it isn't memory safe and doesn't have RAII so I'm not that interested myself at this point.

I guess Ada could be an option too, but I don't know nearly enough about it to say much.

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Zig doesn't have exceptions, it has error unions, so basically functions return either a value or an error code and the caller is forced by the language to note which was returned. And instead of RAII it has defer ... which of course can easily be forgotten or mis-scoped, so it's not safe.

>"Yes that is annoying, but I don't know of any mainstream systems language that does. C and C++ can also have allocations anywhere, and C++ have exceptions."

C++ has a way to tell to compiler that the function would raise no exceptions. Obviously it is not a guarantee that at runtime exception will not happen. In that case the program would just terminate. So it is up to a programmer to turn on some brain activity to decide should they mark function as one or not.

Tbh I’ve found that whenever I’ve hit MAX RAM, failed allocations are not the biggest problem you should be focusing at that time.

Sure, it would be nice to get an error, but usually the biggest threat to your system as a whole is the unapologetic OOM Killer

While this is 100% true for the system allocator, hitting OOM there you're likely hosed, it isn't true if you're using arenas. I work on games and being able to respond to OOM is important as in many places I'm allocating from arenas that it is very possible to exhaust under normal conditions.

For allocation, Zig and Odin. Zig is explicit and Odin is implicit.

> Zig is explicit

i never got this point. whats stopping me from writing a function like this in zig?

  fn very_bad_func() !i32 {
      var GPA = std.heap.GeneralPurposeAllocator(.{}){};
      var gpa = GPA.allocator();
      var s = try gpa.alloc(i32, 1000);
      s[0] = 7;
      return s[0];
  }

the only thing explicit about zig approach is having ready-to-use allocator definitons in the std library. if you excluded std library and write your own allocators, you could have an even better api in rust compared to zig thanks to actual shared behaviour features (traits). explicit allocation is a library feature, not a language feature.

the explicit part is that zig forces you to import allocator of your choosing whereas odin has allocator passed as part of hidden context and you can change/access it only if you want to. hence explicit behavior vs implicit behavior.

i use neither of those languages, so don't ask me for technical details :D

You can require allocations in Odin to be explicit using `#+vet explicit-allocators`

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