[kevincox]

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();

[maxbond]

Would look very similar with named arguments, no?

[svieira]

Not if you do what Dart did: https://medium.com/dartlang/making-dart-a-better-language-fo...

[kevincox]

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.

[maxbond]

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.