Zig in 30 Minutes
gist.github.com
gist.github.com
If I may here are three additional pieces of information that if added to your documentation will clarify some more things for the beginner/reader:
1) Arrays and Slices section
Arrays in Zig are values. They store the pointer and the length, but an array is a value so the raw pointer can never be accesses unless....
You coerce the array to a slice. A slice reveals a pointer to you.
2) Add tagged unions (I do not understand what they are but they exist, maybe some fellow reader here could help me)
3) If, for, while and switch can ALSO BE EXPRESSIONS!
Now to the part that does not address you directly but everyone.
These tutorials are great, but they are the mere starting point. I admire Zig and its design, I admire Andrew and that awesome community, I love Zig Showtime and everything. But there are two problems I have with Zig that annoy me and that is only because I REALLY want to learn it and ditch C already:
* I am trying to figure out how to do system's programming. Like use all the system calls and their system library wrapper equivalent's that I am so used to in C. After an hour of research on the net I could not even figure out how to read in and go through the contents of a file (fread, fstat, fgets, fopen). That stuff needs to go into the official documentation or at least to ziglearn.org
* The same way the Zig compiler is awesome the underlying build file you often wanna write is just horribly documented. I don't understand half of it and it changes a lot. Andrew should really politely ask people on the internet to take down old repos and blog entries. Please document the build system and build file writing better.
Another upside with Zig coming from the embedded world is Zigs idea of doing async/await - since you define the building blocks yourself, it’s really easy to create an async/await-implementation e.g. on top of epoll, but for those times when your hacking on bare metal, you can just write an implementation which fits that particular hardware. It’s really, really good.
It is probably a matter of terminology. For some reason different languages see fit to give the same thing different names.
A union is a type that can be one of several different things. In C unions, there is no built-in way to tell which of those things any given union instance is at any given moment, which can lead to code assuming it is one thing when it is actually another. Tagged unions carry an enum with that that tells you which thing they are right now. Zig will not let you work with a tagged union's value unless you switch on the enum (tag) so you know what you're working with.
> * The same way the Zig compiler is awesome the underlying build file you often wanna write is just horribly documented. I don't understand half of it and it changes a lot. Andrew should really politely ask people on the internet to take down old repos and blog entries. Please document the build system and build file writing better.
Agree wholeheartedly. I've never even bothered to use zig build in years of working with zig because of it. Granted, I make it a rule to rethink what I'm doing if I actually need a complicated set of build steps, but sill.
The language itself is fantastic once you get a decent grasp of it, which you'll probably achieve by reading the stdlib source to get a feel for what you need to do.
I've been using it to build stuff on my Pi Zero. Still hit a few snags with cross compilation and C interop, but it's been a pleasure to write. I'm definitely keeping an eye on it as a good alternative to getting into Rust.
https://ziglearn.org/chapter-2/#filesystem
And details on reading the next line here:
https://ziglearn.org/chapter-2/#readers-and-writers
fread/fstat/fgets/fopen is now all covered. The build system is something I need to cover much more thoroughly, but is something that will take a long time.
What you're asking is absolutely reasonable and I agree that these are things that should exist. The blocker (for the things that I control / can contribute to) is mostly effort and resulting value.
I considered the idea of working on a book that would do a proper introduction. It's something that would be useful, without a doubt, but the problem is that it would take a lot of effort and time (given my current skillset) and it would take away from other possibilities that in my estimate would be more cost-effective for the project.
So the TLDR is that we're genuinely thinking constantly of what's the next best move to make and, given the situation the project is right now, we think other things have to take priority. Of course we could be making a wrong estimate, so we're open to discussing it, but we have to follow the path of least resistance, which means making temporary compromises.
My bet is that if we play our cards well there will be enough skilled communicators interested in writing Zig programming manuals, we just have to get there first :)
I also want one day to write a book on comptime, hopefully it won't take too long!
This is the thing I love so much and if you guys combine this absolutely amazing attitude with some professional marketing I just see a bright, bright future for the Zig language.
I tried all the so called C replacements, and especially Rust. The Zig language is the only approach where one does not need an IQ of a 130 to learn it. Just please you guys do everything to not vanish into a absolute niche like D did, because D was and in my opinion still is such a great candidate/language, they just should have done better marketing.
I would be looking forward for your book and would be the very first one to buy it!!! Also, can I donate to ziglearn, Zig Showtime and/or the Zig Foundation?
In my opinion Linus should think about letting Zig into the kernel and not Rust :D. Maybe one day you guys will also achieve that.
Thank you again, we try :)
If you want to support the ZSF, here you can find all the information you need: https://ziglang.org/zsf/ I'm the one answering mails to donations@ziglang.org, btw.
For ziglearn and Zig Showtime, I guess you should check our respective GitHub profiles.
There is an example here for a kind of iterator.
The status quo for iterators is this:
var it = getSomeIterable();
while (it.next()) |item| {
...
}
IMO it's "good but not great" (not great because it adds a var and the variable pollutes the outer scope). But the alternative is a bit of a pandora's box.I understand where it's coming from, but having something like "for (i32 i in [0,n[)" would be so much nicer in my opinion.
You can do:
var i: usize = 0;
while (i < 10) : (i += 1) {
...
}
or var i: usize = 0;
while (i < 10) {
defer i += 1;
...
}
although the two have slightly different semantics (the latter would increment even after a break; the former wouldn't).Honestly, I'm not sure why people think it is such a big deal. I've written a lot of zig, mostly gamedev stuff, and I rarely use that construction. I find that the vast majority of loops are over arrays or slices.
(The biggest thing I've hit that I want is a way to return information with an error. If that were fixed, I think Zig's error handling would be perfect.)
But the answer there is basically, "if you care about payload, don't use zig's built-in error handling." Which, obviously, you can do, but I'm not convinced it's a great answer!
Even for something as simple as parseInt, it would be nice, I would argue, if it returned, along with InvalidCharacter, which character was invalid. This would enable e.g. very precise indications in messages to the end user of what was wrong with the input.
In general, because currently it's super-ergonomic to return just error codes but more of a pain to return errors w/ payloads, what you'll get in practice is no error payload even when it would be useful, which will end up turning into less-helpful-than-ideal errors for end users, which is contrary to zig's goal of enabling the creation of perfect software. :-)
I found this thread interesting
Just thinking out loud, given Zig's errors primarily allow the compiler to enforce that errors are handled, and exhaustively, beyond that why can't error payloads just be passed as an input argument pointer to the function call? Maybe this is a dumb idea, but it's what C programs already do, except C programs don't have the safety of compiler checked errors offered by Zig. Does the Zig compiler need to check error payloads beyond the type system already provided? I'm not sure.
I agree with you that having such a super-ergonomic error handling system will direct most code towards a certain style, but I don't think this is contrary to Zig's goals of perfect software or simplicity. It's already such a huge win on top of C's error handling.
Yeah, that's definitely a reasonable way to do it, and actually Andrew gives an example of this:
https://github.com/ziglang/zig/issues/2647#issuecomment-5898...
(Andrew's example is slightly different in that rather than an explicit argument, it's an optional field in one of the arguments.)
So it's definitely not like crazy bad or anything, but also definitely less ergonomic than if you could directly return a payload with the error, and this is enough friction that it feels like you'll end up not having error information when you want it (both as an API consumer and eventually as an end-user looking at an error message).
But, I'm still very new to Zig, so perhaps my instincts on that are wrong. :-)
Maybe you're right too! Just speaking for myself here, but as a programmer and "man with a hammer", I sometimes like to think that instincts might just be our mental machine learning model, where it can be really well trained and give the right black box answer, albeit not with the explanatory backstory or rationale, but worth trusting nevertheless.
I'm also new to Zig, and there are ways that a pointer input arg as error payload could go wrong. I'm following the proposal issue, and it will be interesting to see which way it goes.
var it = a.getSomeIterable();
while (it.next()) |item| {
...
}
var it2 = b.getSomeIterable();
while (it2.next()) |item| {
...
} {
var it = a.getSomeIterable();
while (it.next()) |item| {
...
}
}
{
var it = b.getSomeIterable();
while (it.next()) |item| {
...
}
} get size
allocate slice
for(slice) |*elem| elem.* = read()In second case, it's "defer", coming from Go, the language which chickened out to add normal exceptions, because they're "implicit transfer of control", and LOLishly added "defer", as if it's not such.
They absolutely don't. All control paths are explicitly represented by syntax (no different from the hidden goto in a while loop -- it's explicitly recognised by the while syntax); proof: you can draw all of them by just examining the syntax of the current subroutine, while knowing nothing about others. Exceptions, however, are implicit: any call, foo(), might or might not cause some control flow change in the client without there being any explicit acknowledgement of that by the client; you cannot draw all the flow paths just by examining the syntax of the current subroutine.
res, exc = fun();
if (exc) goto exception_handler;
That's underlying model of how exceptions behave, and how they're implemented "manually" in languages with no exception handling (C, Go). You absolutely can draw that by examining syntax of a subroutine, and it's no more implicit than "defer".It's only C's syntax which is truly explicit. It's literally a structured machine-independent assembler. That's why it's gold language which is very hard to displace (it's already perfect for what it is). But just as everyone I'm watching with popcorn all the contenders popping up. (My humble opinion about Zig's issues on that path, I, together with other people, expressed here.)
Its implicitness is zero -- there is zero information not available in the syntax of the current block, exactly as in C -- so I don't see how it can be high compared to anything. You just don't have it in C, so you're not used to it. This is exactly like an Assembly programmer who says that C's `while` is implicit because there is no explicit jmp. In fact, the third clause in C's `for` header works almost exactly like defer: you write a piece of code that isn't executed immediately after the preceding one, but is injected to the end of the block.
A language with `while` isn't any more implicit than a language with just goto; it just has another explicit control-flow construct. Same goes for defer.
> It's literally a structured machine-independent assembler.
Not so much once you take the preprocessor into account.
> it's already perfect for what it is
I think that was true in 1970, not today. First, we know more. Second, we write much bigger programs. Third, "structured assembly" isn't as valuable as it was now that even machine code is "high level." This is not to say that C could be replaced everywhere, but I think, intertia aside, it could be replaced almost everywhere.
Ah, so your mind's window is single block, that what you bang on. You know, blocks can be long too. To the end of reading 1000-line block, you think that you know how it ends. But oops, you completely forgot about some "defer", which implicitly executes at the end of block. That's my definition of "true explicitness", where all code which executes at some point is available locally.
And if you forgo that definition of explicitness, why stop at block? Exceptions work across blocks, i.e. on the level of the entire subroutine, and not much harder to reason about than "defer".
> In fact, the third clause in C's `for` header works almost exactly like defer
Good point. It's a clause in "for", so best practice is to use it for "loop iteration expression". It's also familiar syntax to the entire generations of programmers. Unlike Zig's "2nd clause in while" which is "original design" people will "thank" you for.
> it could be replaced almost everywhere.
The question is with what. IMHO, Zig isn't good enough to replace C at all. Too much NIH, again. It does too much differently. Naive thinking is of course "so that it's better", but actually, it just repeats C's mistakes (ugliness in language) and makes its own, "very original" ones.
But no control flow construct satisfies that. Jumps are the whole point, and the unit for structured control flow is the block (what's the next instruction after `break`, `continue` or `}`?). defer is just as structured, just as local, and just as explicit as C's control flow constructs.
> It's also familiar syntax to the entire generations of programmers.
True, but learning Zig takes a day; two tops. Where it differs in syntax from C, it does so for good reason, and it's not like it's a complex language where different syntax is an additional burden. C's `for` syntax just doesn't make sense (`;`, which everywhere else in the language denotes sequential composition, means something different in the `for` header). Is an additional 2 minutes of learning, in a language that has very little syntax, not worth fixing something that's unpleasant in C?
Talk about confusing, implicit syntax of Zig - there's no connection between "it.next()" and "|item|". It's implicit and you need to make it up. Compare that to other languages: "for item in it" or "while (item = it.next())".
The for loop payload syntax, where you can also give a name to the counter, is the only weirdness with it.
I understand such a strategy (among many possible), and that will be a fun strategy if it pans out. The current situation though is that people question: why that dude purposely make it harder than needed for everyone?
Let's say `for (x in y) {}` replaced the payload operator. It would still exist in:
- if(some_error_union) |value| {} else |err| {}
- if(some_nullable) |value| {}
- while(some_nullable) |value| {}
- switch(some_tagged_union) { .some_tag => |value| {} }
And any that I might be forgetting. Is your suggestion that each of these should have separate syntax, thus complicating the language with one-off syntax?
I'm a human, and syntax is very important to me. 't broken read can syntax I. In that regard, if you purposely (or naively) misuse Comic Sans, then yes, "I don't like the font".
> (which IIRC was taken from Ruby or something).
Bingo. Ruby's not everyone's favorite language, so please be ready that people will send you rays of some hard love in that regard. Did you consider using C syntax for C-replacement-wannabe? (Rhetoric question.)
That's a valid reason to not want to use the language, but I don't believe it is a valid basis for criticism and certainly doesn't excuse the hostility of your comments in this thread.
I assume you mean a natural language. No, I won't complain about a real language used by people. I might criticize someone's inventing their own natural language. The same as I do for programming languages. And I'm very well familiar with the "we need to invent to move forward" argument. I also assume that people taking that ungrateful task are aware that they will receive criticism for that.
> just that it isn't the syntax you're used to.
Not just me, but many people. I specifically started to comment, seeing other people's feedback resonates with my own sentiment about Zig.
> certainly doesn't excuse the hostility of your comments in this thread.
I don't think there was particular "hostility", but I indeed try to nail right at the spot of the issues. Ouch! Beyond that, I allowed me some sour comments regarding downvoting other peoples' and my comments where concerns were raised with way Zig does some things. Such downvoting could be considered hostility, but I actually consider it funny ;-).
Let's look at some of your criticisms:
> @call(.{ .modifier = .never_inline }, collectNoInline, .{gc});
> I'm sorry, but that's total nonsense. Shows that not enough good faith went into Zig design. Even in C, that could be syntactically annotated as: > /*pragma:noinline*/
> collectNoInline(gc);
In which you say that a built-in function call with optional flags and settings is total nonsense, while hijacking comment syntax to change compiler behavior is better. You can make an argument for that, but the way you describe it as "total nonsense" and not in good faith is definitely hostile.Let's look at some more examples:
> Jumping thru hoops is what Zig seems to choose with its unorthodox, different-just-to-be-different syntax.
> Zig appears to have strong NIH mentality in regard to the syntax. Trying to replace C, but go out of their way trying to invent syntax just to be different from it and most other things too.
Zig's syntax isn't that unorthodox except compared to languages that look even more like C than it does, and it definitely isn't different just to be different. By claiming such, when there are thousands of posts in discussions about syntax, is plain insulting. Can you provide even a single post that suggests anyone has ever suggested syntax be a certain way just to be different?
Syntax is not irrelevant to the main use of a programming language the way fonts are to the use someone is probably concerned with if they ask an opinion of a screenplay, so, no, I don't see a similarity there.
> it took me less than a minute to understand the payload operator (which IIRC was taken from Ruby or something).
Loosely inspired by Ruby, perhaps, but definitely not taken from. Neither the positioning nor the semantics are the same.
That's just not true. It is not only pretty exceptional in its general partial evaluation construct combined with compile-time introspection (although D and Nim have some similar features), it is the only language AFAIK where a single general partial evaluation construct is used in stead of type generics, value generics, typeclasses/concepts, constexprs, macros and conditional compilation.
Zig might not be your cup of tea, and that's fine, but it is without a doubt unique in its design and not only special, but pretty radical.
> Talk about confusing, implicit syntax of Zig
I don't think it's any more confusing than any other syntax (and less confusing than C's `for` syntax where the ubiquitous `;` is treated differently than anywhere else), even though it might not be familiar to you before learning it, but there is absolutely nothing implicit here. You might find `in` more appealing to you or more familiar than `|` but it's certainly not more explicit.
Zig offers a radical design. It seeks to be as simple as C — which is particularly important in low-level programming for both portability [1] and humans and machine analysis — while also giving you safety and high expressivity. Obviously, radical design means doing things differently.
Zig rejects any kind of implicitness; all calls must appear as calls. This means no operator overloading, no destructors, and no magical traits. It does so, however, without giving up on expressivity by using other mechanisms.
All low-level programming languages suffer from low abstraction. That comes with the territory. By that I mean that implementation details (especially around memory management) are hard to hide. Changing those details in some component often require changing the clients of that component as well. But C++ and Rust have a design philosophy that tries to hide this intrinsic quality of low-level programming by making the final code appear on the page as if it has abstraction capabilities similar to high-level languages. Of course, that illusion breaks as soon as you try to change code, and it's debatable whether this design helps or harms program comprehension. Zig rejects the C++ philosophy in favour of a brand new, and pretty revolutionary one, that reimagines how low-level programming is done. Unlike Rust, Zig isn't a cleaned-up C++ with a few extra tricks, but it isn't a new C, either. It's something completely different.
You might prefer Zig's design for this domain (as I do) or you might prefer the more traditional C++ design, but the great thing is that Zig is so simple and easy to learn that it's easy to try and find out.
[1]: Consider what it would take to port C++ (or a C++-like language) to new microcontroller you build. You would either need to port LLVM or an extremely complex compiler — a huge undertaking. This is why C (well, there's a tiny bit of Ada, too) still reigns supreme even in domains where correctness is of utmost importance: https://youtu.be/uqan23518Yc?t=632
The more I use Rust the more I am convinced I can write high level performant code. I mean it's ridiculous that sometimes I forget I am writing Rust and not Scala!!
As someone who does a lot of low-level development, before Zig I didn't think any approach other than that of C or that of C++ was even possible. I don't know if Zig will fulfil its promise, but its radical design, that's unlike anything we've ever seen, sure offers a fresh perspective on things.
As to static guarantees -- they are never the point; they are a means to an end: writing more correct programs. That goal is just as valued by Zig as it is by Rust, Zig just tries to achieve it differently. Which achieves it better? It's hard to know right now. I have little doubt that Rust could make things that are today written in C++ safer, but I have serious doubts whether it would be adopted in truly safety-critical domains, where C is king. I think Zig could be.
I didn't know Zig can provide memory safety using it's features. If that's the case it's great, I need to try it out! Although I am sceptical about the claim that in truly safety-critical domains Rust would not be adopted where Zig would, but I am again out of my depth here, so :)
Yes, although this is done through runtime checks (that can be optionally disabled) rather than through static sound guarantees (Rust uses runtime checks in some cases, too). The language's simplicity and fast compilation helps with other types of correctness, too (i.e. beyond memory safety).
> Although I am sceptical about the claim that in truly safety-critical domains Rust would not be adopted where Zig would
I don't know if Zig would, but Rust has several problems for such domains that C and Zig don't: porting it is a challenge (both Rust itself and LLVM are very complex), understanding what a program does is a challenge (a lot of implicit behaviour), and handling allocation failures is a challenge.
Zig also has the same issue with LLVM until the language is fully bootstraped and the original LLVM based compiler no longer part of the build process.
However, packaging a C and C++ compiler alongside for the ride doesn't make it that much simpler.
That might not matter. Porting Rust might not be a simple undertaking, either.
> Zig also has the same issue with LLVM until the language is fully bootstraped and the original LLVM based compiler no longer part of the build process.
Yes, but that's expected to happen before 1.0.
> However, packaging a C and C++ compiler alongside for the ride doesn't make it that much simpler.
C isn't an issue at all; C++ is. I'm pretty sure it could be made optional.
Procedural macros are also somewhat insane in many ways.
It seeks too, but fails. Comparing to really-simple C, it's full of arcane stuff.
> Zig rejects any kind of implicitness; all calls must appear as calls.
We already have that in C.
> Of course, that illusion breaks as soon as you try to change code
That's one of the traits of Zig too it seems. My favorite example of Zig's poor design is following case:
Suppose you have a function call:
collectNoInline(gc);
And you want to annotate it for being never-inlined (call-site level annotation for "always inline" and "never inline" is a customary enough task in low-level programming). So, in Zig, annotated call transforms too: @call(.{ .modifier = .never_inline }, collectNoInline, .{gc});
Ref: https://ziglang.org/documentation/master/#callI'm sorry, but that's total nonsense. Shows that not enough good faith went into Zig design. Even in C, that could be syntactically annotated as:
/*pragma:noinline*/
collectNoInline(gc);I think it's quite the opposite. Don't forget that C also has macros and a lot of arcane undefined behaviour. I don't know if Zig is as simple as C -- it doesn't have macros but does have, say, slices and comptime -- but it's also much safer and much more expressive. Overall, it's a very simple language, that's very expressive and also quite safe.
> That's one of the traits of Zig too it seems.
Absolutely! It's a feature of all low-level languages. Zig, however, unlike C++ and Rust, doesn't try to waste its complexity budget on making it seem like a high-level language when you just look at the code on the page (and it has other downsides, too, besides language complexity).
> I'm sorry, but that's total nonsense. Shows that not enough good faith went into Zig design. Even in C, that could be syntactically annotated as:
And I'm sorry, too, but I would say it's an example of Zig's exceptionally great design at this stage. If at some point it turns out that adding a new kind of syntax element here is worthwhile, it can always be added later. When in doubt -- leave it out. You never know when your complexity budget is best spent, and if you already have a general means of doing something without a new syntactic category, it's best to wait and see.
C lexic-based "macros" are implemented by a separate component, "C preprocessor". C clearly needs a AST-based macros, not a whole new language to replace it. Undefined behavior comes from the fact that C is machine-independent assembler (with structured syntax), so to be exactly that ("machine-independent" and "assembler"), it has to underspecify machine-specific matters, like what happens if you shift 32-bit number by 33 bits.
> I don't know if Zig is as simple as C -- it doesn't have macros but does have, say, slices and comptime -- but it's also much safer and much more expressive. Overall, it's a very simple language, that's very expressive and also quite safe.
Those are points which I doubt - it's clearly not expressive enough, and there're safer languages either. Is there niche for it? I'm on a fence with popcorn. But as I look to it, I see things which I consider "mistakes". And I love to talk about mistakes!
> And I'm sorry, too, but I would say it's an example of Zig's exceptionally great design at this stage.
Expectedly, I don't buy this "worse is better" argument either. It's not good when you annotate a simple call and it turns from a simple call into an ugly mess. It's not rocket science to come with a syntax which would avoid that. If Zig language creators didn't do that so far, that's exactly what I call "not enough good faith went into Zig design".
Your appendix of "so far" is accepted - keep up the great work!
But that "whole new language" is probably smaller than just AST macros for C. And C's problems aren't solved just by fixing macros (I think AST macros are a horrible feature in almost any language that isn't a Lisp; I see them as a sign that the language designers just gave up).
> Undefined behavior comes from the fact that C is machine-independent assembler
True, but that's almost never a valuable thing these days; you lose portability and get little in return other than a somewhat smaller compiler.
> it's clearly not expressive enough
It's at least as expressive as any other low-level language. Any C++/Rust program -- with generics, concepts, destructors, async, traits, macros -- could be translated to an equivalent Zig program that's at worst no longer than some (small) constant multiple of the original. That's not true for C (at least not without hurting performance).
> and there're safer languages either
Low-level? Not so sure. The goal is a language that makes it easy to write correct programs, not "a safe language". I'm not sure there are languages that do that better.
> I don't buy this "worse is better" argument either
It's an "it's just better" argument. Good design is not about picking arbitrary things and making them more convenient, but about spending a certain budget in a way that yields a good gestalt.
> It's not rocket science to come with a syntax which would avoid that.
Sure, but you can add that syntax at any time. It's not urgent. It's best to see if you could perhaps generalise it in some way and get a better return, or maybe invest your complexity budget more wisely elsewhere. I doubt compiler directives make up more than 0.1% of a program.
> If Zig language creators didn't do that so far, that's exactly what I call "not enough good faith went into Zig design".
I've been programming for ~30 years, and aside from Scheme -- maybe -- I don't think I've ever encountered a better-designed language than Zig. Of course, this perception is subjective.
Why is this ".{x}" and not just "x"?
This syntax is used tens of times in the following code snippets but never explained.
This is the kind of information that your tutorial needs to contain, because it's radically different from C and other languages, and this is exactly the kind of information that readers will be looking for: "How different is Zig from C and why should I care?".
Does this mean that zig doesn't support varargs? If not, why not?
Again, another question that a lot of people coming to your page will be asking themselves, please don't take that as a criticism, just candid feedback to help you make your article better.
Zig does not support varargs, except when calling C functions.
Why is just "x" not allowed? What does ".{x}" actually mean?
It all makes a lot more sense after understanding Zig's comptime features:
https://ziglang.org/documentation/master/#comptime
The end of the comptime section also explains how string formatting works that way.
https://ziglang.org/documentation/master/
And the (fairly new, and still a bit thin) std library documentation
https://ziglang.org/documentation/master/std/#std
...gives a good enough rundown to start writing real-world code if you're coming from another C-like programming language.
Zig's std lib documentation will keep getting better. In the meantime, the std lib code itself is so well written, it's worth a read, even coming from another language, and even if you have no intention to learn Zig. I found it easy to read and was impressed by the code structure and quality of the design.
Of course, that's not to suggest that code is documentation, but I've learned alot about improving my programming in general, just by reading Zig's std lib.
I love this quote, adding it to my quote list; is it from something?
Zig the language, and Zig the std lib have two different sets of documentation. The former is really, really good, and I wouldn't say lacking at all, considering Zig is still pre-1.0. Take a look here: https://ziglang.org/documentation/master/
It's the Zig std lib auto-generated documentation (i.e. I/O things like epoll and io_uring and much more) that is incomplete, and to which most of the "documentation is lacking" and "read the std lib source" comments relate.
It's only if you want to know how to use Zig for things like I/O, then you'll need to read the std lib source (and the growing number of blog posts and talks etc), in the same way that K&R is also not always helpful as a guide for these things (and others) today in C.
But the Zig language itself is pretty easy to grok from the excellent language documentation and examples already linked to.
Bonus question: I have a function doing a transformation on this array, what is the way to duplicate this array
- parsing command line arguments
- logging (loglevels, files, stdout/stderr, etc.)
- talking to a restful service via HTTP
Thanks in advance!
https://ziglearn.org/chapter-2/#iterators
I don't think that going further into parsing is in scope. std.log is something that definitely needs to be covered. HTTP, I'm not sure about as it requires a lot of extra machinery outside of the standard library and these things aren't mature yet.
That doesn't seem to be true. The example below this sentence errors because the function foo being used doesn't exist, not because the variable is undefined. A proper example [1] shows that Zig will happily use uninitialized memory here:
x: -1431655766
[1]: https://godbolt.org/z/36j4ab> [Once a variable is set to undefined], it is no longer possible to detect that the value is undefined. undefined means the value could be anything, even something that is nonsense according to the type. Translated into English, undefined means "Not a meaningful value. Using this value would be a bug. The value will be unused, or overwritten before being used."
> In Debug mode, Zig writes 0xaa bytes to undefined memory. This is to catch bugs early, and to help detect use of undefined memory in a debugger.
The @import method is only for "importing" C headers with declarations and have them automatically converted to Zig interface declarations (so in most cases you don't need manually maintained language bindings). For compiling the associated C soure files, Zig has a builtin C compiler.
For regular Zig source files, you just import them into other Zig source files, up to the "main file". Such imports are wrapped into a module struct (imported modules are just regular structs). The Zig build system takes care of efficiently compiling all this with proper incremental build support (one can explore the zig-cache subdirectory which is maintained by the zig compiler for details).
For example, these are the imports in a top-level file:
https://github.com/floooh/pacman.zig/blob/ed42fad79c3e9b4432...
The sokol.zig file groups other modules under a common namespace:
https://github.com/floooh/pacman.zig/blob/main/src/sokol/sok...
...which in turn imports "leaf modules" like this:
https://github.com/floooh/pacman.zig/blob/main/src/sokol/aud...
...it's one of the most straightforward module systems I've seen yet in any language.
An incremental compilation feature is coming to the self-hosted compiler: https://kristoff.it/blog/zig-new-relationship-llvm/
https://github.com/floooh/pacman.zig
...and before that I did the same in C99 (might be useful for comparing the languages):
https://github.com/floooh/pacman.c
Disclaimer: I'm not a Zig expert at all, and the project doesn't really require most Zig features that differ from C. But I think writing small and "for-fun" projects like this is important for getting used to a language. I think one of Zig's big qualities is that it is so straightforward, after a few hundred lines you hardly have to look up things in the language documentation anymore.
We're serious in the sense of very much alpha, and with a long way to go, hopefully intersecting with Zig's stability program in the next year or so, but we have some demos and benchmarks in there of using Zig for io_uring. Zig's std lib already has io_uring helpers based on liburing's design, which we contributed.
We would have gone with C for its ABI, OOM-safety and control over memory layout, but considered Zig ready enough given our own medium term timeline, and the developer velocity and safety is already paying off. We also wanted a fantastic compiler, which Zig already provides. I personally wouldn't go back to C for a new project like this.
It's named "Futureproof": https://www.mattkeeter.com/projects/futureproof/
Anyone who has dug into these care to comment about the pros and cons of each?
rust: more like a safe c++, you can get all the performance of c or c++ with the memory safety of a garbage collected language, as well as data race safety and nulls do bot exist. downsides are it can be a hard to learn paradigm to satisfy the compile time memory checks, and it is slower to compile
nim: sort of like a statically typed python. fun syntax and features, compiles to C, quickly. has in the past used garbage collection but a new reference counting mechanism has been introduced lately.
If anyone has an idea about the (A) relative stability of the languages, and (B) the number of libraries/packages for things you don't want to write yourself, that'd be great.
Note:
> has in the past used garbage collection but a new reference counting mechanism has been introduced lately.
Reference counting is a kind of garbage collection. It's often faster than the "hello world" of gc, namely mark and sweep, but it has its own challenges.
Anyway, I don't think production readiness of a language that hasn't reached 1.0 really matters.
It might be better to publish a lot of stuff about a single topic, where it can attract interested groups and build enough that it actually proves the merits of the language.
Edit: punctuation
```
std.debug.print("hello world!\n", .{});
```that kind of extra typing is what turn me off to be very honest, other than that, zig seems like C and Swift had a baby, pretty nice
another thing:
```
const LikeAnObject = struct{
value: i32,
fn print(self: *LikeAnObject) void {
std.debug.print("value: {}\n", .{self.value});
}
};```
Why don't make the self: *LikeAnObject implicit?
Again, this focus on extra typing only just add noise in my opinion, function is already wrapped inside the struct, i feel like it HAS to be implicit
-- EDIT --
One last thing:
```
for (array) | value | {
std.debug.print("array {}\n", .{value});
}
```Not a fan of the | | syntax, it doesn't feel natural
```
for (value in array)
```Here it is pretty clear what it does
-- EDIT 2 --
```
const std = @import("std");
std.debug.print("hello\n", .{});
```
is import the right word here? feels like it should be ``use`` since you'll use them this way: ``std.debug.print``
``import`` would be to make all the types directly visible and use this way: ``debug.print``
The || syntax is used elsewhere in zig, if statements, catch, switch, etc.
There's no requirement for a function inside a struct to act on the contents of structs, so it's reasonable to use structs as namespaces. This is what is happening when you @import, for example. The imported file becomes a struct.
This is quite different from a lot of other PLs, but it is pleasantly consistent when you get used to it.
There is a usingnamespace keyword to make a structs public contents spill out into the current scope. It's to be used sparingly.
Edit: I'm wrong! It's an anonymous struct with number fields, not an anonymous array.
also why ask for a parameter when it is not needed? print vs printf in C
Consider the above code without it:
std.debug.print("hello world!\n", struct{}{});
Now add a value: std.debug.print("{}!\n", struct{string: []const u8}{ .string = "hello world"});
Quite unwieldy. Zig used to have variadic functions and it was difficult to work with, complicated metaprogramming, and made how things work less obvious during reading. It was also pretty much only ever used for the "print" function.It's compile-time checked. The example shows a compile time error when the struct fields are not completed by the anonymous struct
Edit: also, the print stuff, I feel that’s in line with the Zig Zen - make the language simple to understand. Now the print function has a very clear type. Otherwise you need a “smart” print function (like Rust does with a macro or C does with varargs). Easier to understand, not easier to type.
Why its not int64, int32, unsigned_int32, vec, function for all language, but inventors have to change these to u64, i64, fn...etc?
Jumping thru hoops is what Zig seems to choose with its unorthodox, different-just-to-be-different syntax. I wonder, how many will want to jump with it?
Did zig run over your dog or something? You seem to be particularly hostile in your comments about it. As someone who has participated in discussions about zig syntax for years, I can assure you that a significant amount of thought and consideration goes into these choices. It is not "different-just-to-be-different". In fact, the very syntax being complained about is derived from other languages!
Having said that, less typing and clutter are also beneficial, so it's really a net natural debate.
Personally I prefer it, mostly for subjective reasons but I think it makes sense - in the case of Rust it was the easiest syntactic novelty to get used to, things like lifetime annotations are a different beast.
When people do something differently than most other popular implementation it's good to ask if that's worth it.
"i32" and "u32" are used because they are short (and used often). They are just typedef away in C and are used ~forever, did you look at Linux kernel for example?
But I'm with you on the general sentiment - beyond trivial, lexical things like type names (which almost any language allows you to redefine anyway), Zig appears to have strong NIH mentality in regard to the syntax. Trying to replace C, but go out of their way trying to invent syntax just to be different from it and most other things too.
And a lot of people appear to notice and pay attention to this, as the discussion here shows.
Languages have many competing goals. It shouldn't take long to get used to u64 over, e.g., unsigned_int64, and brevity is valuable in its own right. Too many wasted characters can obscure the flow of a program and make it slower to read and understand.
Is it the right choice? I could be persuaded either way. I know it's one I've personally made before, choosing rebindings like i256 and cmpeq8 when doing a lot of bit-twiddly vector code.