shape_warrior_t

joined 10 months ago
 

Saw this on Lobsters, thought Lemmy might enjoy it.

[–] shape_warrior_t@programming.dev 0 points 2 months ago (1 children)

Not very familiar with the libraries, and BB_C has already given a lot of more detailed feedback, but here are some small things:

  • Even without rewriting get_files_in_dir as a single chain of method calls, you can still replace
    if dir.is_err() {  
        return None  
    };
    // use dir.unwrap()
    
    with
    let Ok(dir) = dir else {
        return None;
    };
    // use dir
    
    In general, if you can use if let or let else to pattern match, prefer that over unwrapping -- Clippy has a lint relating to this, actually.
  • Although the formatting doesn't seem horrible, it doesn't seem like Rustfmt was used on it. You might want to make use of it for slightly more consistent formatting. I mainly noticed the lack of trailing commas, and the lack of semicolons after return None in get_files_in_dir.
 

We adopted Rust for its security and are seeing a 1000x reduction in memory safety vulnerability density compared to Android’s C and C++ code. But the biggest surprise was Rust's impact on software delivery. With Rust changes having a 4x lower rollback rate and spending 25% less time in code review, the safer path is now also the faster one.

(Emphasis in original.)

Of course, we should probably take the numbers with a grain of salt here; it's not a controlled scientific experiment, and the estimated vulnerability density for Rust in particular was calculated with a numerator of 1, so it could be way off.

Still, I think it's a good reminder that advocacy for using Rust over C and C++ isn't purely out of some irrational fanboy-ism for the language. The numbers here would have to be extremely off for there not to be a major effect.

Further down in the article:

This near-miss inevitably raises the question: "If Rust can have memory safety vulnerabilities, then what’s the point?"

The point is that the density is drastically lower. So much lower that it represents a major shift in security posture. Based on our near-miss, we can make a conservative estimate. With roughly 5 million lines of Rust in the Android platform and one potential memory safety vulnerability found (and fixed pre-release), our estimated vulnerability density for Rust is 0.2 vuln per 1 million lines (MLOC).

Our historical data for C and C++ shows a density of closer to 1,000 memory safety vulnerabilities per MLOC. Our Rust code is currently tracking at a density orders of magnitude lower: a more than 1000x reduction.

[–] shape_warrior_t@programming.dev 0 points 7 months ago (2 children)

The fact that x += y modifies lists in place might be surprising if you're expecting it to be exactly equivalent to x = x + y.

[–] shape_warrior_t@programming.dev 0 points 7 months ago (2 children)

There was a recent langdev Stack Exchange question about this very topic. It's a bit trickier to design than it might seem at first.

Suppose we require a keyword -- say var -- before all binding patterns. This results in having to write things like
for (&(var x1, var y1, var z1), &(var x2, var y2, var z2)) in points.iter().tuple_windows() {},
which is quite a bit more verbose than the current
for (&(x1, y1, z1), &(x2, y2, z2)) in points.iter().tuple_windows() {}.
Not to mention you'll have to write let var x = 0; just to declare a variable, unless you redesign the language to allow you to just write var x = 0 (and if you do that, you'll also have to somehow support a coherent way to express if let Some(x) = arr.pop() {} and let Some(x) = arr.pop() else {todo!()}).

Suppose we require a keyword -- say const -- before all value-matching patterns that look like variables. Then, what's currently

match (left.next(), right.next()) {
    (Some(l), Some(r)) => {}
    (Some(l), None) => {}
    (None, Some(r)) => {}
    (None, None) => {}
}

turns into either the inconsistently ugly

match (left.next(), right.next()) {
    (Some(l), Some(r)) => {}
    (Some(l), const None) => {}
    (const None, Some(r)) => {}
    (const None, const None) => {}
}

or the even more verbose

match (left.next(), right.next()) {
    (const Some(l), const Some(r)) => {}
    (const Some(l), const None) => {}
    (const None, const Some(r)) => {}
    (const None, const None) => {}
}

and you always run the risk of forgetting a const and accidentally binding a new match-all variable named None -- the main footgun that syntactically distinguishing binding and value-matching patterns was meant to avoid in the first place.

Suppose we require a sigil such as $ before one type of pattern. Probably the best solution in my opinion, but that's one symbol that can no longer be used for other things in a pattern context. Also, if you're already using sigils before variable names for other purposes (I've been sketching out a language where a pointer variable $x can be auto-dereferenced by writing x), doubling up is really unpleasant.

...So I can understand why Rust chose to give the same, most concise possible syntax for both binding and value-matching patterns. At least compiler warnings (unused, non-snake-case variables) are there to provide some protection from accidentally turning one into the other.

 

A nice little reminder that clarity is not the same as verbosity. Also has some concrete tips for removing unnecessary verbosity in names, complete with examples. Though in some contexts, I might prefer a name like employeeToRole for a Map<Employee, Role> over the article's employeeRoles.

 

I think this is a decently interesting consideration in programming language design. When you have things flowing from left to right, not only do you get better autocomplete as per the article, but it's probably also easier to read, and very likely easier to edit (your cursor can simply go in its natural direction instead of having to jump around).

Though this comment on Lobsters points out that left-to-right code under one way of thinking is not necessarily left-to-right code if you approach it with a different way of thinking.

[–] shape_warrior_t@programming.dev 9 points 8 months ago* (last edited 8 months ago) (2 children)

I was thinking of the three legal states as:

  • not logged in (null or {isAdmin: false, isLoggedIn: false})
  • logged in as non-admin (false or {isAdmin: false, isLoggedIn: true})
  • logged in as admin (true or {isAdmin: true, isLoggedIn: true})

which leaves {isAdmin: true, isLoggedIn: false} as an invalid, nonsensical state. (How would you know the user's an admin if they're not logged in?) Of course, in a different context, all four states could potentially be distinctly meaningful.

[–] shape_warrior_t@programming.dev 1 points 8 months ago (1 children)

My preferred way of modelling this would probably be something like
role: "admin" | "regular" | "logged-out"
or
type Role = "admin" | "regular";
role: Role | null
depending on whether being logged out is a state on the same level as being a logged-in (non-)admin. In a language like Rust,
enum Role {Admin, Regular}
instead of just using strings.

I wouldn't consider performance here unless it clearly mattered, certainly not enough to use
role: number,
which is just about the least type-safe solution possible. Perhaps
role: typeof ADMIN | typeof REGULAR | typeof LOGGED_OUT
with appropriately defined constants might be okay, though.

Disclaimer: neither a professional programmer nor someone who regularly writes TypeScript as of now.

[–] shape_warrior_t@programming.dev 5 points 8 months ago (1 children)

a === b returns true if a and b have the same type and are considered equal, and false otherwise. If a is null and b is a boolean, it will simply return false.

[–] shape_warrior_t@programming.dev 34 points 8 months ago (4 children)

I would certainly rather see this than {isAdmin: bool; isLoggedIn: bool}. With boolean | null, at least illegal states are unrepresentable... even if the legal states are represented in an... interesting way.

[–] shape_warrior_t@programming.dev 0 points 9 months ago* (last edited 9 months ago) (1 children)

Nice! Some feedback (on your Python, I don't speak Greek):

  • In Python, the idiomatic way to name variables and functions is snake_case -- for example, greekTranslation should be greek_translation. (EDIT after seeing your most recent reply: good luck with that when it comes to Python :) )
  • You're currently recomputing reverseTranslation every time the user requests an English-to-Greek translation. Unless you're planning to modify greekTranslation while the program is running, it would likely be more efficient to make reverseTranslation a global variable, computed just once at the start of the program.
  • The control flow in the main program could be a bit more clear:
    • The condition in while optionSelection == <'practice'/'translation'> makes it look like optionSelection could change to something else inside the loop, yet you never do so. You could just write while True instead.
    • Instead of putting the "Please select either practice, translate, or exit" check up front, it would likely be more maintainable to add it as an else branch to the main if-elif-elif chain. That way, if you added in a new option, you would only have one place in the code to modify instead of two. (Also, instead of x != a and x != b and x != c, you could write x not in [a, b, c]).
    • Speaking of the if-elif-elif chain, you could replace it with a match statement, which would remove the repetitions of optionSelection ==.

Here's how I would write the control flow for the last section:

    optionSelection = input().strip().lower()
    match optionSelection:
        case 'practice':
            while True:
                practiceGreek()
                print('')
                print('Would you like another? [yes] [no]')
                print('')
                selection = input().strip().lower()
                print('')
                if selection != 'yes':
                    break
        case 'translate':
            while True:
                translateToGreek()
                print('')
                print('Would you like to translate another phrase? [yes] [no]')
                print('')
                selection = input().strip().lower()
                print('')
                if selection != 'yes':
                    break
        case 'exit':
            print('')
            print('Thank you for using the Greek Practice Program!')
            print('')
            sys.exit()
        case _:
            print('')
            print('Please select either practice, translate, or exit')
            print('')

(You could probably pull the while True loops into their own dedicated functions, actually.)

Hope that helps. Feel free to ask if any of this doesn't make sense.

[–] shape_warrior_t@programming.dev 19 points 9 months ago (2 children)

Even regular Rust code is more "exciting" than Python in this regard, since you have a choice between self, &self, and &mut self. And occasionally mut self, &'a self, and even self: Box<Self>. All of which offer different semantics depending on what exactly you're trying to do.

 

Found this article via a comment on Lobsters for a completely different article. It's not exactly the type of knowledge I see myself using in the immediate future, but I think it's still interesting and educational to think about.

You can get the exclusive behaviour with random.randrange. (Relevant Stack Overflow question with a somewhat interesting answer)

[–] shape_warrior_t@programming.dev 0 points 9 months ago* (last edited 9 months ago)

Probably a good idea, but not one that fits my current vision of the game, unfortunately. Especially since my main idea for adding complexity is increasing the number of sides (square->pentagon->hexagon), so each level already has a different-looking playfield.

...Right, I kind of forgot that the directory structure for my repo doesn't need to look anything like the directory structure of the releases. Thanks for prompting me to think about that.

 

Just wanted to publicly announce this project at this point in time. All the info is on the GitHub page. If you have any feedback, or find any bugs or issues, please let me know in the comments.

 

An interesting article that lays out a problem and goes through a few different solutions, some of which I haven't thought about much before.

I'm working on a video game in Rust, and I'm running into this kind of modelling problem when it comes to keeping track of the game state. So far I've refactored something that resembles Approach 5 into something that looks more like Approach 3. As I get more confident about the final shape of the data, it (seemingly) becomes a better idea to represent it in a more structured way.

 

Thoughts? It does feel like there's a lot of things you can do in comments that would be impossible or impractical to do in names alone, even outside of using comments as documentation. There's certainly much more information that you can comfortably fit into a comment compared to a name.

One of the comments in the Lobste.rs post that I got this from stuck out to me in particular:

Funny story: the other day I found an old zip among my backups that contained the source code of game that I wrote 23 years ago. I was just learning to code at the time. For some reason that I forgot, I decided to comment almost every single line of that game. There are comments everywhere, even for the most obvious things. Later on, I learned that an excess of comments is actually not considered a good practice. I learned that comments might be a code smell indicating that the code is not very clear. Good code should be so clear, that it doesn’t need comments. So I started to do my best to write clear code and I mostly stopped writing comments. Doing so only for the very few parts that were cryptic or hacky or had a very weird reason for being there.

But then I found this old code full of comments. And I thought it was wonderful. It was so easy to read, so easy to understand. Then I contrasted this with my current hobby project, which I write on an off. I had abandoned it for quite some months and I was struggling to understand my own code. I’ve done my best to write clear code, but I wish I had written more comments.

And this is even worse at work, where I have to spend a ton of time reading code that others wrote. I’m sure the authors did their best to write clear code, but I often find myself scratching my head. I cherish the moment when I find some piece of code with comments explaining things. Why they did certain things, how their high level algorithm works, what does this variable do, why I’m not supposed to make that change that looks like it will simplify things but it will break a corner case.

So, I’m starting to think that this idea that comments are not such a good practice is actually quite bad. I don’t think I can remember ever reading some code and thinking “argh so many comments! so noisy” But, on the other hand, I do find myself often in the situation where I don’t understand things and I wish there were some more comments. Now I’m trying to write comments more liberally, and I think you should do the same.

I guess that’s a generalization of the op’s idea.

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