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Comment by rapsey | Hacker News Reader

Also nothing prevents you from using Rust without higher abstractions.

If you are part of development community, you also get to read other people's code, use libraries, and so forth. When I open a C file it can be written without care certain times, but C is so self-evident that it's hard to don't understand the code after some superficial reading.

I think C is misleadingly easy: it's easy to reason about, say, a single function body since there's only so many things you can even write in C.

But when you start composing things together and juggling the lifetimes of various things, the complexity balloons and it becomes a lot harder to understand "spooky action at a distance"-type things. You might argue that with good structure and discipline it's still not difficult, but the assumptions are all implicit and you have to get into the mind of whoever wrote it in the first place to understand it. And I write a lot of C and still find it tricky when I have to go look at some random C codebase!

I agree, but what I said has very little to do with that. What you says means that poorly written code has unexpected bugs. But you understand what it does, easily.

If the bugs are unexpected then it's hard to understand what it does :-)

Isn't it more like, you understand the tiny portion of the source code easily, that fits on the screen/in your head?

> I write a lot of C and still find it tricky when I have to go look at some random C codebase

Absolutely. C Code is not necessarily easy to understand. Not at all.

But the C parts itself are? In C you seldom wonder what C does, you wonder what the C code does.

If you work like OP likes, single person projects, small enough to keep almost completely in your head, I can see how C is especially charming. You never wrangle with C, only with your own code.

> but C is so self-evident that it's hard to don't understand the code after some superficial reading

You do realise that C and C++ are among the languages (there is also Perl) having anual obfuscated writing contests, right?

Being self evident is certainly not something I associate with C code.

I believe that "self evidence" parent comment mentions is something that only comes from years upon years of learning all the pitfalls of writing C.

That sound like a challenge

Superficial reading will tell you absolutely nothing about the code the macro processor creates from the bytes you see.

This leads to the same problem as in the C++ world: a fragmentation of the library ecosystem because of wildly different opinions on what "proper C++" actually is.

What would examples of such fragmentation (i.e. overlapping libraries notably distinguished by what kind of C++ they use) in the C++ ecosystem be?

One example: There's a lot of JSON parsing libraries across the whole spectrum, from using the latest C++ features, or exceptions for error handling, or various subsets of stdlib types, etc... down to essentially being "C with namespaces".

But usually the most controversial features are:

- use of exceptions

- use of RTTI and dynamic_cast

- use of stdlib types which allocate memory under the hood

- ...or even use of any stdlib types

- has boost or similar complex dependencies

- use of 'modern C++' features that explode compile times (like the range stuff)

...etc etc... when you look at C++ libraries written in the game development or embedded hemisphere, those usually use an entirely different C++ subset than the more academic "modern C++" crowd.

The deep-embedded/real-time compatible features I'd agree, that's really a different ecosystem, but that is the case in every language (assuming the language can even be used in such environments). Other than that I don't see it come up very often in practice as something that makes or breaks a library choice.

Rust has explicit subsets of its standard library:

* core, whose only dependencies are six symbols (memcpy, memcmp, memset, strlen, rust_begin_panic, and rust_eh_personality)

* alloc, which layers on top of core, and adds the ability to allocate memory

* std, which includes all of the operating system specific things

But most importantly, you can declare that your code doesn't require std and alloc with an annotation, and there's a way to tag these crates in the package manager as well. Additionally, cargo has a "features" feature, so you can say "please give me the no_std version of the library" and get what fits within your needs.

My team at work is working purely in the 'core' subset, and we're able to easily find and evaluate open source projects that will work for us, because of this.

Oh, I should also mention: while Rust doesn't have exceptions, there's also a way to compile your program so that panics abort instead of unwind the stack, similar to -fno-exceptions being passed when compiling C++ code. There is also a setting you can include so that, if, for some reason, you require the unwinding semantics, if someone tries to build a project with abort semantics and your program, it will not allow it and let you know why. I don't think I've ever seen this annotation on a package in the wild, because since they're not used in the regular course of programming in Rust, virtually every open source library does not use them for important semantics and so therefore works with either setting.

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