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Comment by cute_boi | Hacker News Reader

"Rust makes hard things easy and easy things hard."

Disagree here. Like article Rust 2018 is very nice and ergonomic. Iterators, Lifetime Elision etc are nice to work.

Regarding noise many people consider those noise but I find noises like return types etc very useful. Because I can be sure the return type. Regarding actual code actix doesn't look that bad from examples also.

I use warp and its pleasant to work. The only thing I hate is compilation time other than that I don't think I have any major criticism against rust. But compilation time is near to cpp etc so ...

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I'm a recent Rust fan (via AoC), but for "easy things hard", I would offer input/string processing as an example— regexes, string operations, grammar, etc. I know that Rust is forcing me to be correct and handle (or explicitly acknowledge that I'm not handling) my error cases, but from the point of view of just wanting to get the happy path working, it's a lot more noise to deal with compared with what it would look like in Python, eg:

        let re = Regex::new("(?P<min>[0-9]+)-(?P<max>[0-9]+) (?P<letter>[a-z]): (?P<password>[a-z]*)").unwrap();
        re.captures_iter(&contents).map(|caps|
            Input {
                password: caps.name("password").unwrap().as_str().to_string(),
                letter: caps.name("letter").unwrap().as_str().chars().next().unwrap(),
                min: caps.name("min").unwrap().as_str().parse().unwrap(),
                max: caps.name("max").unwrap().as_str().parse().unwrap()
            }
        ).collect()

If you get rid of unwrap and use `if let` and `match`, this code will clean up nicely.

If the code is supposed to be maintainable, you could also make something like a FromRegex trait for Input. It would be a good idea to try exercism's mentoring thing to get better at writing it the easier way the first time. The mentoring thing really is what helped me to think in ways that made this mess easier to avoid.

Fair fair. To be honest, I think in a lot of these cases there are good helper crates/macros; for this I would now probably use recap: https://docs.rs/recap/0.1.1/recap/

The really horrendous scenario was when I was trying to navigate pest iterators for parsing according to a grammar.

Even without if let or match many of those unwraps are unnecessary. See https://github.com/zookini/aoc-2020/blob/master/src/bin/2.rs

Interesting! Can you help me understand why this doesn't work for me?

    error[E0599]: no method named `parse` found for enum `Option<regex::Match<'_>>` in the current scope
      --> src\main.rs:24:39
       |
    24 |                 min: caps.name("min").parse().unwrap(),
       |                                       ^^^^^ method not found in `Option<regex::Match<'_>>`

I think you need .name("min")?.as_str() to access the underlying text of the match object (after making sure it is a valid match with the ?), which can then be parsed. The regex Match object itself does not have a parse method that I can see.

I don't know what the structure Input looks like but I played around with your code and it seems to work with as_str()

https://play.rust-lang.org/?version=stable&mode=debug&editio...

caps.name("min") returns an Option which you need to handle e.g. by unwrapping. You can use caps["min"] instead if you don't want an option.

See this is what I'm talking about. This is ridiculous.

Actual code examples from Actix isn’t that bad but take a look at the docs.

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