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What does assign a generic in a trait?
(lemmy.world)
Maybe the question is not well written, but it's because I do not really know what's happening in here. I'm learning Rust, I'm doing pretty good, but this is the second time that stomp with this.
First, I thought that only the Add trait would be enough, but the LSP keep saying me this if I do not add the "restriction", as far as I know.
What I do not get is what <Output = T> is. I know that is using the type T, but why it is assigned to Output?
The first time that I saw something similar was in the Rust book that comes with rustup, just look at the next function signature
Thank you for you help, you are awesome.
@capuccino You're not assigning anything. The Output = T is expressing a constraint. It's saying that the addition of T has to result in T again. A type can implement Add with any output type it wants.
@capuccino An alternative is to not use T: Add<Output = T>, but to replace your usage of T, where it represents the output type, with <T as Add>::Output
I found it in the book. Is in advanced chapters, near the end, dang. Thank you for your time!