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Comment by est31 | Hacker News Reader

You have any concrete examples? I'm not very familiar with swift, so I opened a random file in the project [0]. On the first glance it feels like the typical noisy OOP java code base. Probably most of it done with automated tools. Very weird were the named arguments repeating the same thing [1]. Would have been much shorter in Rust as it doesn't have named arguments (and IMO Rust should never get them). And on the first half of the file there are a bunch of POD struct definitions with a few init functions. In Rust, those POD structs where all members are public can be easily be initialized without having to create functions for it (but then you do have to name the "arguments", but for struct initializers I don't consider it to be a problem). So way less repetition.

[0]: https://github.com/apple/swift-nio-ssh/blob/main/Sources/NIO...

[1]: https://github.com/apple/swift-nio-ssh/blob/8a75ab90e1b12182...

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Named arguments is a HUGE thing for ergonomics. It makes code many times more readable, since it automatically documents intent much more clearly. The code linked here is nowhere near representative of regular Swift code.

As a very basic made-up example, the real value of named arguments is code like this:

    FileManager.copy(path1, path2)

What does that do? There is no way to tell which file is copied to which. In Swift, this is written as:

    FileManager.copy(from: path1, to: path2)

Suddenly, there is no need to look up the function to figure out what it does. It is perfectly clear.

The first use I recall for named parameters was in Algol60. One could write:

  copyfile(path1)to:(path2)

Instead of:

  copyfile(path1, path2)

I always liked that idea, but found Objective-C’s version of this less attractive. Smalltalk had named parameters too. Algol60, to me, had the nicest syntax for this.

Swift has improved nicely on the Objective-C style, I think.

If you were being "idiomatic," you'd probably write it like so:

    MyOwnFileManager.copyFileFrom(_ path1: String, to path2: String)

Apple has started to make it like that.

No, that is the old Objective-C style. It is definitely not idiomatic.

In the more recent Swift and library releases, I have had to change my code to fit the above pattern, as I get deprecation errors all the time.

But you are correct that it started with ObjC. That doesn't make it a bad thing. It seems that Apple is starting to circle back.

I prefer the initial one that you posited. I'm pretty sure the Swift style guide suggests the way you mentioned, and not the ObjC way.

BTW: I deleted the post where I talk about where I saw this. It seems folks just want to argue, and that's not why I come here.

I've not seen any of these in years now. Where have they been popping up?

> and IMO Rust should never get them

I guess whatever floats your boat. Personally, I enjoy not having to write functions like doStuff(true, true, true, false) or alternatively define types for every single boolean flag I want to have. Terseness is a non goal for Swift.

> And on the first half of the file there are a bunch of POD struct definitions with a few init functions.

I don't know how rust handles this but in swift, each POD struct has an implicit member wise constructor visible from the file it's defined. This is for encapsulation purposes, as its signature of course changes if you add fields to the struct.

> Personally, I enjoy not having to write functions like doStuff(true, true, true, false)

Yeah that's not beautiful, but most of my code is rather

doStuff(foo, bar, baz)

where foo, bar and baz are descriptive variable names. I agree that it's hard to understand with literals, but in the rare cases you need such flags you can either have a config struct or use the builder pattern. Also, nowadays you can set up vscode to use the rust-analyzer LSP plugin, which shows you the types as well as the parameter names. But of course that doesn't work on Github and similar places.

IDK in general, the people who want named arguments outnumber the people who don't want them, at least in threads about the question, which obviously preselects the people who want them. Maybe eventually Rust will get them, no idea. But IMO that code shows how named arguments can make code more noisy than before.

> I don't know how rust handles this but in swift, each POD struct has an implicit member wise constructor visible from the file it's defined. This is for encapsulation purposes, as its signature of course changes if you add fields to the struct.

In Rust, POD structs can be constructed iff all their members are visible through the publicity system to the code that tries to construct them. If it's in a different crate, it's also important whether there is a #[non_exhaustive] attribute on the struct declaration or not.

> where foo, bar and baz are descriptive variable names

But descriptive variable names should describe what those variables ARE, not how they are going to be passed to a function.

So, does copy(tempFile, databaseFile) copy the temporary file over the database file, or vice versa?

"Typical noisy OOP java code base", without a single class in the whole file, only value types. As for automated tools, I think you're giving Xcode too much credit. It'll help you a bit, but not much.

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