Tl;dr: It is just pointer dereferencing.
I.e. C's
*ptr
ptr.*
I.e. C's
*ptr
ptr.*
Edit: Going through this author's website, it seems like a lot of their posts are about rediscovering low-level programming concepts through Zig. Like this article, where they discover you can't compare strings directly, and you have to use memcmp:
https://www.openmymind.net/Switching-On-Strings-In-Zig/
They claim that they blog because they "find that [they] retain things better when I write about them." No problem with that. Just a little odd to see on the hn front page, I suppose.
I think this is just "discovering". While you (and I) probably discovered these things with assembly or C languages, it's perfectly reasonable or even appropriate for newer generations to have these kinds of experiences with Zig or Rust.
When I took my first programming class at RIT, visualizing the stack, variables, and pointers was one of the first classes we had. It's one of those beginner diagrams that I feel like everyone is familiar with. But I can understand that there are programming domains with equivalent complexity which don't require that base knowledge. I apologize if I came off as elitist.
It's more topical than many articles posted here imo. But topical is in the eye of the beholder.
https://news.ycombinator.com/newswelcome.html
Deeply interesting tech, or otherwise.
When learning piano you first learn how to play rudiments and then you move up to more complex scores.
Otherwise you end up writing an article about how Ravel' Scarbo is amazing because it involves playing with two hands at the same time.
If learning Piano was an example then everyone would have like you said learn the basic of everything and then build up on it. Modern day people learn multiple different chords and somehow string them together. If you do EE you have have learned how the piano works before you start playing the piano.
Worth remembering most people in programming today start with Javascript / Python or Ruby.
Those languages are hardly more abstract than learning Lisp or Prolog back in the day, other than (with exception of JavaScript) finally embracing dynamic compilers.
It boils down to how much one actually cares to learn and is curious to improve themselves.
More common with guitar than piano though.
Similarly they are most popular with Javascript than with C
Are there really that many Zig programmers that have never seen C or know what pointers are?
But, to answer your question directly: absolutely. In addition to writing a lot about it, I maintain some popular libraries and lurk in various communities. Let me assure you, beginner memory-related questions come up _all the time_. I'd break them down into three groups:
1 - Young developers who might have a bit of experience in JavaScript or python. Not sure how they're finding their way to Zig. Maybe from HN, maybe to do game development. I think some come to Zig specifically to learn this kind of stuff (I've always believed most programmers should know C. Learning Zig gets you the same fundamentals, and has a lot of QoL stuff).
2 - Hobbyist. Often python developers, often doing embedded stuff. Might be looking to write extensions in Zig (versus having to do it in C).
3 - Old programmers who have been using higher level languages for _decades_ and need a refresher. Hey, that's me!
Also, from learning human languages, it's a well-known lesson that phrasebook-type "this means this" translations (like some here are asking, from Zig to C/Rust) are useful for quick and dirty learning good enough for one trip, but long term learning needs this kind of a direct explanation.
1. It avoids the word (or syntax in this case) getting stuck in a double-indirection state, needing you to mentally translate it from Zig to C to what it actually means every time.
2. It avoids the learner attaching the wrong nuances to the word or syntax feature, based on the translation they're given, when the language they're learning has different nuances. In other words, it helps the learner see it as its own thing, and not be unduly colored by what they already know and find easy to grasp on to (even when it's subtly wrong).
This is also good when the user already knows the concept. Like, I'm a reasonably competent Rust user, and when I started playing around with Zig I already understood the majority of concepts at play and just needed to know how Zig spelled them. But I still needed that more in-depth explanation for concepts I was less familiar with (comptime being the main one).
Lots of popular Youtubers such as Primeagen (somebody who easily gets 200/300k+ views per video) have been speaking highly about Zig.
Perhaps some day Zig will have replaced C and beginners will come to Zig having never touched C, and in that context this approach makes sense - after all, you wouldn't litter an introductory article on C with comparisons to Algol. But today, surely the modal Zig beginner already knows enough C that the syntax would better be explained by reference to C.
You aren't always the target.
Sometimes it seems like the change is just to make it different, not better.
The whole point of Zig is to fix C's mistakes. I don't know why they'd repeat this one.
I wish they'd got it right for (de)referencing too though.
It’s not that important though. Many people write two or more languages without mixing the syntax.
p.* and lv.& would be good post-operators, imo. Less going left and parenthesizing.
The alternative to if-else would be something like `assuming-otherwise`.
The point was that there wasn’t really a pressing need to reinvent the *p/&p syntax.
—Andreas Rumpf
Ada does the same exact thing, except there you write `p.all` instead.
In any case, while the exact syntax may not be ideal, using a postfix operator for dereferencing is vastly better than prefix in practice due to typical patterns of use. There's a reason why you end up writing () a lot in C code with heavy pointer operations - the things they end up mixed with most often turn out to have the wrong kind of priority and/or precedence more often than not. Things are much simpler when everything is postfix and code reads naturally left-to-right.
x()->g()->f();
All it requires is that the function returns a pointer to a struct which itself contains function pointers.
C also allows the dot form if you really want it:
x().g().f()
Now to make it a bit more usable, one needs a bit of planning so that either of these can be done:
x(&x_out).g(&g_out, x_out).f(&f_out, g_out);
x(&x_out)->g(&g_out, x_out)->f(&f_out, g_out);
Where there is a VFT in each of the xxx_out structures, and the calls simply returns the VFT, while the whole abstraction is stored/returned via the out arguments.
f(*g(*x)) is just as good as f(g(x*)*)
Hmm, function names go before parentheses, that looks like a good reason for dereferencing to be prefix too, otherwise they end up a long way apart.
But in the back of mind I'm thinking "semantics cause pointless fussy arguments, all code is ugly, let's stop programming in text somehow".
But this is literally not semantics. Semantics is everything of value, this is just syntax.
is it a method call? is it a property/field value? how am i to be indicated that there is an implicit suspend point when you .await?
In the ideal world, we wouldn't have unary prefix operators at all, but unfortunately unary +, -, and NOT are prefix mostly because they were that in math notation and got grandfathered in (bonus points to Smalltalk here for going with consistency here - "not" and "negated" are regular nullary methods there so it's postfix throughout!). However, these are rarely themselves an operand of another unary operator, so you can mostly deal with this by giving postfix higher precedence than prefix in all cases, so at least it's a simple rule. But then for pointer dereference, it is in fact common to have the result of a dereference itself be an operand in the middle of another expression.
So now you have some choices to make. If you make the pointer dereference prefix, then you don't need extra parentheses when applying other prefix operators to it, e.g. -*p or !*p. If you make it postfix, then you don't need extra parentheses when applying other postfix operators to it, e.g. (using Pascal-style ^ for dereferencing) p^[0] or p^.x. Alternatively, you could add special postfix operators that desugar into the combination but avoid those extra parens, which is what C did with -> for field access.
(Technically, you could also make everything prefix instead, e.g. field access ALGOL 68 style: `month OF birthDate OF person`. But this is very counter-intuitive with indexing, and also makes code completion unusable, so it's not a serious option.)
bar = await foo()
await bar.coro(*args)
Although I agree that await could use some precedence like new in javascript:
new types.Date().toJSON()
// fine
await readdir(…).filter(…)
// oops
Neither, honestly. They both look terrible.
when a value is dereferenced, having a consistent left to right dereferencing makes sense.
for example, in c, without looking up the order of operations how confident are you that you know what is going on in the following:
foo = **bar[10]
(Yes, C programmers will probably hunt you down if you do this, but it does work.)
This syntax is less arbitrary than C's. It draws a syntactic parallel between accessing a single member and accessing "all members". (by using pattern-matching-like syntax)
It makes the language more consistent and one's mental model of it smaller. (Even though I doubt that patterns other than the Kleene star would work)
A parallel with files:
cp dir/a dir/b dir/c /other/dir
cp dir/* /other/dir
cp *dir /other/dirBut it seems like I'm in the minority, so maybe it's just "old man shouts at clouds", I'll just ignore the language and move on :)
In Zig, you can pretty much read the types aloud and it makes, your brain does not need to peek for parsing. For me it's too late, I got used to the C way but I still want the better thing to get adopted. No more int ((foo)(int))[5]; nonsense—just T, [N]T, or *T, making intent crystal clear.
I happen to be reading the K&R C book right now and they do in fact tell you this.
That said, C's function pointer declaration syntax is indeed awful. But really that's because ANSI took a very hardline "no incompatible changes" tact when adding prototypes to the language, which limited the ways they could express them. That decision is one of the reasons we're still writing C today. Any yahoo can come up with a new language, kids do it all the time. ANSI's job was to add features to the language in which Unix was already written.
I have not read it so that's on me I guess
ptr.*.*
?This Is basically the gist of the article.
I’m surprised to see that so many programmers these days don’t know C and basic pointers.
Large parts of the industry does really work with low(er) level languages.
Even people who went through C/C++ in their formal education/start of their career may have not used it for a long time.