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A comment on Rust 1.64.0. Parent comment

Re:Rust 1.64.0 by kevincox on Thursday September 22, 2022 @01:32PM (#32942081)
It gets awkward really fast when you may need to set a value.

    let mut foo = build_foo()
        .with_a(8);

    if need_to_set_b {
        foo = foo.with_b(false);
    }

    let foo = foo.build();
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Re:Rust 1.64.0 by maxbond on Thursday September 22, 2022 @01:44PM (#32942244)
Would look very similar with named arguments, no?
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Re:Rust 1.64.0 by svieira on Thursday September 22, 2022 @02:44PM (#32942967)
Not if you do what Dart did: https://medium.com/dartlang/making-dart-a-better-language-fo...
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Re:Rust 1.64.0 by kevincox on Thursday September 22, 2022 @01:51PM (#32942337)
Maybe. It depends a bit on how they are implemented. If there is a good way to pass "default" then you can just have a condition for that one argument. But if there is no way to pass "default" then it can get hairy.
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Re:Rust 1.64.0 by maxbond on Thursday September 22, 2022 @04:15PM (#32944050)
For sure. I would like to see that in Rust as well, that would be nice. I am willing to put up with the lack of variadic & named arguments for the goodness the borrow checker brings me, but I can see how that would improve the ergonomics substantially.
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