Zen-C: Write like a high-level language, run like C
github.com180 points by simonpure 18 hours ago
180 points by simonpure 18 hours ago
From what I can see in the codegen, defer is not implemented "properly": the deferred statements are only executed when the block exits normally; leaving the block via "return", "break", "continue" (including their labelled variants! those interact subtly with outer defers), or "goto" skips them entirely. Which, arguably, should not happen:
var f = fopen("file.txt", "r");
defer fclose(f);
if fread(&ch, 1, 1, f) <= 0 { return -1; }
return 0;
Did you manage to compile this example?
Yes, actually:
$ cat kekw.zc
include <stdio.h>
fn main() {
var f = fopen("file.txt", "r");
defer fclose(f);
var ch: byte;
if fread(&ch, 1, 1, f) <= 0 { return -1; }
return 0;
}
$ ./zc --emit-c kekw.zc
[zc] Compiling kekw.zc...
$ tail -n 12 out.c
int main()
{
{
__auto_type f = fopen("file.txt", "r");
uint8_t ch;
if ((fread((&ch), 1, 1, f) <= 0)) {
return (-1);
}
return 0;
fclose(f);
}
}> Mutability
> By default, variables are mutable. You can enable Immutable by Default mode using a directive.
> //> immutable-by-default
> var x = 10; > // x = 20; // Error: x is immutable
> var mut y = 10; > y = 20; // OK
Wait, but this means that if I’m reading somebody’s code, I won’t know if variables are mutable or not unless I read the whole file looking for such directive. Imagine if someone even defined custom directives, that doesn’t make it readable.
Yes, sadly, the one billion dollar mistake… I don’t know why the author took this path. it’s so confusing and immediately raised an issue: https://github.com/z-libs/Zen-C/issues/19 And of course, confusion: https://github.com/z-libs/Zen-C/pull/13#issuecomment-3739722... Life is already hard, but apparently not for developers, as I see
Given an option that is configurable, why would the default setting be the one that increases probability of errors?
For some niches the answer is "because the convenience is worth it" (e.g. game jams). But I personally think the error prone option should be opt in for such cases.
Or to be blunt: correctness should not be opt-in. It should be opt-out.
I have considered such a flag for my future language, which I named #explode-randomly-at-runtime ;)
> Or to be blunt: correctness should not be opt-in. It should be opt-out.
One can perfectly fine write correct programs using mutable variables. It's not a security feature, it's a design decision.
That being said, I agree with you that the author should decide if Zen-C should be either mutable or immutable by default, with special syntax for the other case. As it is now, it's confusing when reading code.
But why put it as a global metaswitcher instead of having different type infered from initial assignation qualifier?
Example:
let integer answer be 42 — this is a constant
set integer temperature be 37.2 — this is a mutable
cst ↦ 123 // a constant is just a trivial map
st ← 29.5 // initial assignment inferring float> I have considered such a flag for my future language, which I named #explode-randomly-at-runtime ;)
A classic strategy!
> Given an option that is configurable, why would the default setting be the one that increases probability of errors?
They're objecting to the "given", though. They didn't comment either way on what the default should be.
Why should it be configurable? Who benefits from that? If it's to make it so people don't have to type "var mut" then replace that with something shorter!
(Also neither one is more 'correct')
It's not ideal but it seems like something an LSP could tell you on a hover event. I didn't see an LSP (I didn't look that hard either) but presumably that's within the scope of their mission statement to deliver modern language ergonomics. (But I agree with sibling comments that this should be a keyword. Another decent alternative would be that it's only global in scope.)
Other languages also have non-local qays of influencing compiler behavior, for example attributes in rust (standard) or compiler pragmas in C (non-standard).
When reading working code, it doesn't matter whether the language mode allows variable reassignment. It only matters when you want to change it. And even then, the compiler will yell at you when you do the wrong thing. Testing it out is probably much faster than searching the codebase for a directive. It doesn't seem like a big deal to me.
Yeah, immutability should probably use a `let` keyword and compiler analysis should enforce value semantics on those declarations.
Agreed, using `var` keyword for something that is non-var-ying (aka immutable) is not very intuitive.
Mutability is distinct from variability. In Javascript only because it's a pretty widely known syntax:
const f = (x) => {
const y = x + 1;
return y + 1;
}
I've only glanced at this Zen-C thing but I presume it's the same story.
"immutable variable" is an oxymoron. Just because Javascript did it does not mean every new language has to do it the same way.
There are two distinct constructs that are referred to using the name variable in computer science:
1) A ‘variable’ is an identifier which is bound to a fixed value by a definition;
2) a ‘variable’ is a memory location, or a higher level approximation abstracting over memory locations, which is set to and may be changed to a value by an assignment;
Both of the above are acceptable uses of the word. I am of the mindset that the non-independent existence of these two meanings in both languages and in discourse are a large and fundamental problem.
I take the position that, inspired by mathematics, a variable should mean #1. Thereby making variables immutably bound to a fixed value. Meaning #2 should have some other name and require explicit use thereof.
From the PLT and Maths background, a mutable variable is somewhat oxymoronic. So, I agree let’s not copy JavaScript, but let’s also not be dismissive of the usage of terminology that has long standing meanings (even when the varied meanings of a single term are quite opposite).
“Immutable” and “variable” generally refers to two different aspects of a variable’s lifetime, and they’re compatible with each other.
In a function f(x), x is a variable because each time f is invoked, a different value can be provided for x. But that variable can be immutable within the body of the function. That’s what’s usually being referred to by “immutable variable”.
This terminology is used across many different languages, and has nothing to do with Javascript specifically. For example, it’s common to describe pure functional languages by saying something like “all variables are immutable” (https://wiki.haskell.org/A_brief_introduction_to_Haskell).
It's odd that the async/await syntax _exclusively_ uses threads under the hood. I guess it makes for a straightforward implementation, but in every language I've seen the point of async/await is to use an event loop/cooperative multitasking.
I’d say that the point of async/await is to create a syntax demarcation between functions which may suspend themselves (or be suspended by a supervisory system) and those functions that process through completely and cannot be suspended (particularly by a supervisory system). The means to enable the suspension of computation and allow other computations to proceed following that suspension are implementation details.
So, having an async function run on a separate thread from those functions that are synchronous seems a viable way to achieve the underlying goal of continuous processing in the face of computations that involve waiting for some resource to become available.
I will agree that inspired by C#’s originating and then JavaScripts popularization of the syntax, it is not a stretch to assume async/await is implemented with an event loop (since both languages use such for implementation).
Noob question: if it just compiles to threads, is there any need for special syntax in the first place? My understanding was that no language support should be required for blocking on a thread.
One advantage is that it gives you the opportunity to move to a more sophisticated implementation later without breaking backwards compatibility (assuming the abstraction does not leak).
Async/await should do a little more under the hood than what the typical OS threading APIs provide, for example forwarding function parameters and return values automatically instead of making the user write their own boilerplate structs for that.
Constant hash seed? Never a good idea (std/core.zc)
Syntax aside, how does this compare to Nim? Nim does similar, I think Crystal does as well? Not entirely sure about Crystal tbh. I guess Nim and Vala, since I believe both transpile to C, so you really get "like C" output from both.
From what I see, Zen-C aims to be "C with super-powers". It still uses C pointers for arrays and strings. It transpiles to single human-readable C file without symbol mangling. No safety. Not portable (yet?).
Nim is a full, independent modern language that uses C as one of its backends. It has its own runtime, optional GC, Unicode strings, bounds checking, and a huge stdlib. You write high-level Nim code and it spits out optimized C you usually don't touch.
Here’s a little comparison I put together from what I can find in the readme and code:
Comparison ZenC Nim
written in C Self-Hosted
targets C C, C++, ObjC, JS, LLVM (via nlvm), Native (in-progress)
platforms POSIX Linux, Windows, MacOS, POSIX, baremetal
mm strategy manual/RAII ARC, ORC(ARC with cycle collector), multiple gc, manual
generated code human-readable optimized
mangling no yes
stdlib bare extensive/batteries-included
compile-time code yes yes
macros comptime? AST manipulation
arrays C arrays type and size is retained at all times
strings C strings have capacity and length, support Unicode
bounds-checking no yes (optional)man I haven't heard anything about Vala in ages. is it still actively developed/used? how is it?
Yes, it is actively being developed.
Quite easy to make apps with it and GNOME Builder makes it really easy to package it for distribution (creates a proper flatpak environment, no need to make all the boilerplate). It's quite nice to work with, and make stuff happen. Gtk docs and awful deprecation culture (deprecate functions without any real alternative) are still a PITA though.
Vala is still being developed and used in the GNOME ecosystem. Boo, on the other hand, is pretty dead.
Crystal compiles directly to object code, using LLVM. It does provide the ability to interoperate with C code; as an example, I use this feature to call ncursesw functions from Crystal.
I was also going to mention this reminds me of Vala, which I haven't seen or heard from in 10+ years.
Surprisingly theres a shocking number of GUI programs for Linux made with Vala, and ElementaryOS is built using Vala, and all their custom software uses Vala. So it's not dead, just a little known interesting language. :)
An interesting bit to me is that it compiles to (apparently) readable C, I'm not sure how one would use that to their advantage
I am not too familiar with C - is the idea that it's easier to incrementally have some parts of your codebase in this language, with other parts being in regular C?
one benefit is that a lot of tooling e.g. for verification etc. is built around C.
another is that it only has C runtime requirement, so no weird runtime stuff to impelement if youd say want to run on bare metal..you could output the C code and compile it to your target.
i think so. The biggest hurdle with new languages is that you are cut off from a 3rdparty library ecosystem. Being compatible with C 3rd party libraries is a big win.
Makes it easy to "try before you buy", too. If you decide it's not for you, you can "step out" and keep the generated C code and go from there.
This isn't a very sane plan. The ~300 LOC example mini_grep (https://github.com/z-libs/Zen-C/blob/main/examples/tools/min...) compiles to a ~3.3k LOC monstrosity (https://pastebin.com/raw/6FBSpt1z). It's easier to rewrite the whole thing than going from the generated code.
At least for now, generated code shouldn't be considered something you're ever supposed to interact with.
I looked at it primed for the worst by your comment, but it’s honestly not so bad. A lot of setup, data type code and what looks like overloads.
Initial commit was 24h ago, 363 stars, 20 forks already. Man, this goes fast.
man has been posting a lot before the initial commit about his library. following the guy on linkedin.
Could be bots.
It’s not, it’s just how hackernews works. You’ll see new projects hit 1k-10k stars in a matter of a day. You can have the best project, best article to you but if everyone else doesn’t think so it’ll always be at the bottom. Some luck involved too. Bots upvoting a post not organically I doubt is gonna live long on first page.
That's not how it works. My publication with (subjectively) better language barely had a couple of comments and github stars.
The stars are on GitHub, they can come from somewhere else, e.g. the author himself buying stars.
Hi, I'm the developer's father. Trust me, he hasn't bought a single star in his life—not even in Super Mario :p
Definitely could be, but the dev has been posting updates on Twitter for a while now. It could be just some amount of hype they have built.
Basically C2/C3 but Rust influenced. Missed chance to call it C4.
Impressive repos. I've been toying with the ideas myself but it's hard to stay on track with this sort of extremely demanding task. I am however not exporting to C but to low level jit.
A lot of the ideas in there are worth being inspired by.
So, the point of this language is to be able to write code with high productivity, but with the benefit of compiling it to a low level language? Overall it seems like the language repeats what ZIG does, including the C ABI support, manual memory management with additional ergonomics, comptime feature. The biggest difference that comes to mind quickly is that the creator of Zen-C states that it can allow for the productivity of a high level language.
It has stringly typed macros. It's not comparable to Zig's comptime, even if it calls it comptime:
fn main() {
comptime {
var N = 20;
var fib: long[20];
fib[0] = (long)0;
fib[1] = (long)1;
for var i=2; i<N; i+=1 {
fib[i] = fib[i-1] + fib[i-2];
}
printf("// Generated Fibonacci Sequence\n");
printf("var fibs: int[%d] = [", N);
for var i=0; i<N; i+=1 {
printf("%ld", fib[i]);
if (i < N-1) printf(", ");
}
printf("];\n");
}
print "Compile-time generated Fibonacci sequence:\n";
for i in 0..20 {
print f"fib[{i}] = {fibs[i]}\n";
}
}
The Zig equivalent of the above comptime block just be:
const fibs = comptime blk: {
var f: [20]u64 = undefined;
f[0] = 0;
f[1] = 1;
for (2..f.len) |i| {
f[i] = f[i-1] + f[i-2];
}
break :blk f;
};
I wonder, how can a programming language have the productivity of a high-level language ("write like a high-level language"), if it has manual memory management? This just doesn't add up in my view.
I'm writing my own programming language that tries "Write like a high-level language, run like C.", but it does not have manual memory management. It has reference counting with lightweight borrowing for performance sensitive parts: https://github.com/thomasmueller/bau-lang
C is literally a high level language.
Seriously, in the discussion happening in this thread C is clearly not a high-level language in context.
I get your statement and even agree with it in certain contexts. But in a discussion where high-level languages are presumed (in context) to not have memory management, looping constructs are defined over a semantics inferred range of some given types, overloading of functions (maybe even operators), algebraic datatypes, and other functional language mixins: C most certainly IS NOT a high level language.
This is pedantic to the point of being derailing and in some ways seemed geared to end the discussion occurring by sticking a bar in the conversations spokes.
Nim is a high-level language as well and compiles to C.
Odin and Jai are others.
Does Odin compile to C? I thought it only uses LLVM as a backend
No, Odin does not compile to C. It is a standalone programming language that compiles directly to machine code. It primarily uses LLVM as its backend for compiling to machine code, like you said.
Same question but for Jai.
Jai does not compile to C. It has a bytecode representation that is used primarily for compile time execution of code, a native backend used mostly for iteration speed and debug builds, and a LLVM target for optimized release builds.
chicken scheme compiles to c as well. it's a pretty convenient compilation target, you get to use all the compilers and tool chains out there and you don't add a dependency on llvm
I love CHICKEN Scheme! Nice to see it mentioned. Though I think it's worth pointing out it compiles to something pretty far from handwritten C, to my understanding. I think this is true of both performance and semantics; for example you can return a pointer to a stack allocated struct from a foreign lambda (this is because chicken's generated C code here doesn't really "return", I think. Not an expert).
Of course you can always drop to manually written C yourself and it's still a fantastic language to interop with C. And CHICKEN 6 (still pre-release) improves upon that! E.g structs and Unions can be returned/passed directly by/to foreign functions, and the new CRUNCH extension/subset is supposed to compile to something quite a bit closer to handwritten C; there are even people experimenting with it on embedded devices.
Chicken indeed interoperates with C quite easily and productively. You're right that the generated C code is mostly incomprehensible to humans, but compiles without difficulty.
The Chicken C API has functions/macros that return values and those that don't return. The former include the fabulous embedded API (crunch is an altogether different beast) which I've used in "mixed language" programming to good effect. In such cases Scheme is rather like the essential "glue" that enables the parts written in other languages to work as a whole.
Of course becoming proficient in Scheme programming takes time and effort. I believe it's true that some brains have an affinity for Lispy languages while others don't. Fortunately, there are many ways to write programs to accomplish a given task.
> this is because chicken's generated C code here doesn't really "return", I think. Not an expert.
not an expert either, but you're right about that, it uses cps transformations so that functions never return. there's a nice write up here: https://wiki.call-cc.org/chicken-compilation-process#a-guide...
I am working on mine as well. I think it is very sane to have some activity in this field. I hope we will have high level easy to write code that is fully optimized with very little effort.
There are going to be lots of languages competing with Rust and Zig. It's a popular, underserved market. They'll all have their unique angle.
I has been served for several decades, however since the late-90's many decided reducing to only C and C++ was the way going forward, now the world is rediscovering it doesn't have to be like that.
They're are certainly going to be lots of languages because now with LLMs it's easier (trivial?) to make one + library (case in point: just within last month there're have been posted here ~20 new langs with codebases 20k~100k LOC) but don't really see them competing. Rust and Zig brought actual improvements and are basically replacing usecases that C++/C had limiting the space available to others.
Is it memory safe?
Nice! Compiles in 2s on my unexceptional hardware. But it lacks my other main desiderata in a new language: string interpolation and kebab-case.
Oh, it _does_ have string interpolation, my bad. Sadly, not by default -- you still have to go back and add an "f" before the string once you've started typing it and then realize that you want an interpolated string. Also, it doesn't always work -- if I define two interpolated string variables in one function, GCC chokes in a way I'm not understanding. And every interpolated string variable consumes 4K of global memory.
I wonder how this compares to the Beef programming language.
The Beef programming language was used to write Penny's Big Breakaway.
The author includes some easter-eggs (printing random facts about Zen and various C constructs) which trigger randomly -- check out the file src/zen/zen_facts.c in the repository...
The tagline also applies to C :-)
Is this the Typescript of C ?
That's a very nice project.
List of remarks:
> var ints: int[5] = {1, 2, 3, 4, 5};
> var zeros: [int; 5]; // Zero-initialized
The zero initialized array is not intuitive IMO.
> // Bitfields
If it's deterministically packed.
> Tagged unions
Same, is the memory layout deterministic (and optimized)?
> 2 | 3 => print("Two or Three")
Any reason not to use "2 || 3"?
> Traits
What if I want to remove or override the "trait Drawing for Circle" because the original implementation doesn't fit my constraints? As long as traits are not required to be in a totally different module than the struct I will likely never welcome them in a programming language.
C uses `|` for bitwise OR and `||` for logical OR. I'm assuming this inherited the same operator paradigm since it compiles to C.
The whole language examples seem pretty rational, and I'm especially pleased / shocked by the `loop / repeat 5` examples. I love the idea of having syntax support for "maximum number of iterations", eg:
repeat 3 {
try { curl(...) && break }
except { continue }
}
I guess you could easily emulate it with `for x in range(3): ...break`, but `repeat 3: ...break` feels a bit more like that `print("-"*80)` feature but for loops.
Answering the title, why not Julia?
What's the performance hit?
Example at the top of the readme!
18 commits! I hope you keep up with the project, it’s really cool, great work.
Yet another overly-hyped language with no practical benefits. Is it just another one better C?
Am I the only one who saw this syntax and immediately though "Man, this looks almost identical to Rust with a few slight variations"?
It seems to just be Rust for people who are allergic to using Rust.
It looks like a fun project, but I'm not sure what this adds to the point where people would actually use it over C or just going to Rust.
> what this adds
I guess the point is what is subtracts, instead - answer being the borrow-checker.
> answer being the borrow-checker
There is an entire world in Rust where you never have to touch the borrow-checker or lifetimes at all. You can just clone or move everything, or put everything in an Arc (which is what most other languages are doing anyway). It's very easy to not fight the compiler if you don't want to.
Maybe the real fix for Rust (for people that don't want to care), is just a compiler mode where everything is Arc-by-default?
So it re-adds manual lifetime checking. Got it.
It might or might not be a toy project, I'm not sure, but one advantage of subtracting the borrow checking is that the compiler avoids a lot of complex machinery.
Borrow checking in Rust isn't sound AFAIK, even after all these years, so some of the problems with designing and implementing lifetimes, region checking, and borrow checking algorithms, aren't trivial.
Maybe take the parts of rust the author likes, but still encourages pointers in high level operations?
I thought the same and felt it looked really out of place to have I8 and F32 instead of i8 and f32 when so much else looks just like Rust. Especially when the rest of the types are all lower case.
Agreed, that really stood out as a ... questionable design decision, and felt extremely un-ergonomic which seems to go against the stated goals of the language.
Every language is apparently required to make one specific version of these totally arbitrary choices, like whether to call the keyword function, func, fun, fn, or def. Once they do, it’s a foolish inconsistency with everything else. What if the language supported every syntax?
But at that point why not Rust then?
Why not compile to rust or assembly? C seems like an odd choice.
In fact why not simply write rust to begin with?
Assembly requires way more work than compiling to, say C. Clang and gcc do a lot of the heavy lifting regarding optimisation, spilling values to the stack, etc
Then you're stuck with the C stack, though, and no way to collect garbage.
I have a couple interpreters I've been poking at and one uses 'musttail' while the other uses a trampoline to get around blowing up the C stack when dispatching the operators. As for the GC, the trampoline VM has a full-blown one (with bells-and-whistles like an arena for short lived intermediate results which get pushed/popped by the compiled instructions) while the other (a peg parser VM) just uses an arena as the 'evaluation' is short lived and the output is the only thing really needing tracking so uses reference counting to be (easily) compatible with the Python C-API. No worries about the C stack at all.
I mean, I could have used the C stack as the VM's stack but then you have to worry about blowing up the stack, not having access (without a bunch of hackery, looking at you scheme people) to the values on the stack for GC and whatnot and, I imagine, all the other things you have issues with but it's not needed at all, just make your own (or, you know, tail call) and pretend the C one doesn't exist.
And I've started on another VM which does the traditional stack thing but it's constrained (by the spec) to have a maximum stack depth so isn't too much trouble.
At times people think C is better. See recent discussion about https://sqlite.org/whyc.html
If I understand the history correctly then it started as a set of C preprocessor macros.
[flagged]
> C is the patrician's choice.
Is this suppose to be a positive thing? I thought we all wanted to violently murder the patricians.
Regardless, C might be a valid IR. I apologize for being bigoted.