It's a little verbose (like most of Rust), but I really like this approach. It'll make a lot of logic easier to reason about. I missed that in the article, so thanks for pointing it out.

[–] ISO@lemmy.zip 3 points 19 hours ago (1 children)

(Didn't read the article.)

It's not a secret approach or anything. thiserror gives you that with a simple #[from] attribute annotation on the relevant error variant on your Error enum (which is what your Error type should be).

In your case, this just works because you're not attaching custom context to your error. Usually, you would want to attach some context, and in that case, .map_err()would obviously still be needed, and that's fine. This idea of having to write as little code as possible is stupid.

Sometimes, attaching context once is sufficient, sometimes it's not. If it's the former, then you can still do From in your bigger error enums which have variants from your smaller error enums (e.g. crate-level Error type with variants trivially wrapping module-level Error types).

[–] treadful@lemmy.zip 1 points 12 hours ago (1 children)

This idea of having to write as little code as possible is stupid.

Is it? Not only is it less work, but generally makes the code way easier to reason about. In this case, instead of just seeing simple function calls explaining the logic flow, you visually have to parse all this weird extra cruft that is generally irrelevant to what the block is doing.

[–] jerkface@lemmy.ca 0 points 12 hours ago* (last edited 12 hours ago) (1 children)

Yes, code golf practiced for any reason other than the sheer joy of it is "stupid." It especially doesn't belong in production code. If typing is really so bad, there are any number of local agents that are competent to finish that map fragment for you.

[–] treadful@lemmy.zip 1 points 4 hours ago

It's not about "sheer joy", nor obfuscation. It's about making code easier to write and easier to grok.

[–] gabmus@retrolemmy.com 4 points 23 hours ago

Well, is it really? The verbose part is converting from an error type to another, which you would likely also do in a language with exceptions in the catch block, or in some giant cursed interceptor thing that does a switch/match on the error type (something I had the displeasure to witness with my own two eyes, multiple times)