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Comment by medo-bear | Hacker News Reader

to me the assertion has merit from the point of view that being able to understand what your application does completely is much easier in a small language like C or lisp/scheme, which i believe is essential to maintaining the proper master -> tool relationship with the computer. it seems straigh forward to me that if you use things you dont understand it is likely you will open your application to all sorts of potential unexpected behaviour

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Having worked on C and C++ compilers for a few years at this point: I would say that there’s a strong negative correlation between claiming that C is a simple language and actually understanding C, as specified.

C is actually a fantastically complicated language, both syntactically and at the semantic and abstract machine level.

while i said its small, not simple, i do not think it is controversial to say that c is simplER than rust if what you aim for is a complete understanding of your aplication

I think that is controversial: Rust has more complex syntax than C does, but has a substantially simpler semantic model. Just a small example: given just `T*`, neither you nor your compiler knows what your global aliasing set is. The compiler has to do significantly more work to prove exclusive ownership (necessary for many optimizations), and you have no formal guarantee that your data doesn’t change underneath you.

> Rust has more complex syntax than C does, but has a substantially simpler semantic model

i am not sure i understand, are you saying that c and rust have the same semantics ?

They’re comparable, as evidenced by both being representable within existing compiler IRs. But no, I said that C’s semantics are significantly more complex.

my view of c is as an abstraction over assembly. from this perspective i just cannot see that rust provides simpler semantics, unless you are trying to make c do something which you should probably use another language for, like lisp :)

This is what I mean: C is absolutely not a naive abstraction over assembly. The C standard is clear on this: C is defined in terms of an abstract machine, which in turn doesn’t cleanly map to any particular machine architecture.

Treating C like a “high level assembler” needs a rule like the cryptographic doom principle: it will inevitably lead you astray, and “astray” for C generally means memory unsafety.

> Treating C like a “high level assembler” needs a rule like the cryptographic doom principle: it will inevitably lead you astray, and “astray” for C generally means memory unsafety

you are right. however, i think c does a better job at being a model of an abstract machine than rust. if we restrict semantics to that, and the developer accepts that they need more knowledge than just c, i think the semantics are simpler than rust's. in the same way, dont you think that rust can create a false sense of security to those not completely understanding what protections it provides? if we see programming languages as a hci problem, then i think c by default offers more freedom, and consequently more unsafety. amyway i dont want to come off as hating rust, i think it is a good language, but more importantly its community seems fantastic and i wish it success

> dont you think that rust can create a false sense of security to those not completely understanding what protections it provides?

No: the entire point of Rust's design is that you don't need to know the abstract machine semantics to write Rust safely. The compiler enforces the semantics for you, rather than pushing them onto you.

C on its own does feel like a simpler language though I think it’s true that the semantics taken literally undermine it (the generated assembly can be really surprising sometimes). I do trust a given Rust program to have a specific runtime behavior much more when optimized. It might be interesting to come up with a variant of C that has genuinely simpler semantics as well (not sure how useful I’d find it though)

It’s a common argument that a more simple language makes for more understandable code, yet practical programming tells a different story. From web browsers to every major C compiler, C++ is the language of choice. Similarly for GUI frameworks, GPGPU programming, etc. So what is it? Are we supposed to believe the, frankly pompous, notion that those developers/firms/institutions/etc were tricked? No, I think not.

If we are being honest with ourselves the truth is that even a language as nightmarishly complex as C++ is preferable to C. And whether or not you agree with that the fact is that the world marches on regardless.

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