News for hackers. Stuff that matters.

A comment on Should small Rust structs be passed by-copy or by-borrow?.

Re:Should small Rust structs be passed by-copy or by-borrow? by anderskaseorg on Monday August 26, 2019 @05:57AM (#20798519)
> Blech! Having to explicitly borrow temporary values is super gross.

You can cut down on a lot of that by implementing basic operations (Add, Mul, etc.) for both value and reference types.

    impl Add<Vector3> for Vector3 { … }
    impl Add<&Vector3> for Vector3 { … }
    impl Add<Vector3> for &Vector3 { … }
    impl Add<&Vector3> for &Vector3 { … }
(The first three can delegate to the last one, unless there are value-specific optimizations you want to apply.)
[ Parent | on HN ]
Re:Should small Rust structs be passed by-copy or by-borrow? by crave_ on Monday August 26, 2019 @10:13AM (#20800004)
This has irked me as well. Is there an acceptable way to make this less verbose?

A crate with a derive macro for example?

[ Parent | on HN ]
Re:Should small Rust structs be passed by-copy or by-borrow? by pornel on Monday August 26, 2019 @11:13AM (#20800513)
There is, https://lib.rs/derive_more
[ Parent | on HN ]
Re:Should small Rust structs be passed by-copy or by-borrow? by hcs on Monday August 26, 2019 @11:55AM (#20800858)
As danieldk mentioned elsewhere, you could get partway there with std::borrow::Borrow

    impl<T> Add<T> for &Vector3 where T: Borrow<Vector3>
[ Parent | on HN ]
Re:Should small Rust structs be passed by-copy or by-borrow? by shmerl on Monday August 26, 2019 @03:04PM (#20802686)
Does that essentially overload + for it?
[ Parent | on HN ]
Re:Should small Rust structs be passed by-copy or by-borrow? by saghm on Monday August 26, 2019 @04:11PM (#20803248)
Yes; Rust uses traits to implement behavior for operators on custom types (see the full list here: https://doc.rust-lang.org/std/ops/#traits)
[ Parent | on HN ]