Rust: What the fuck is a borrow checker and why is it yelling at me?

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > The Cavern of COBOL > Rust: What the fuck is a borrow checker and why is it yelling at me?

crazysim: May 23, 2004; I AM SOOOOO GAY

sarehu posted:

I went to a Rust meetup a couple days ago. Seven people showed.

One guy was a C guy asking questions who seemed to have shown up with no idea what Rust was for. He asked what is it for. He also asked if it had as good a prepocessor system as the C preprocessor. Another seemed to know quite a bit about Rust, and other things. Another guy spent the entire time editing some Medium post. We spent the time doing an exercism.io exercise where an object has a mutable String field.

But, as a result, I wrote my actual first self-originated line of Rust code, so there's that!

Edit: On that note, is there any way to make a match pattern redundantly declare the type of a variable? Take for example
code:
pub fn hello(name: Option<&str>) -> String {
    "Hello, ".to_string() + &match name {
        Some(s) => s.to_string(),
        None => "World".to_string()
    } + &"!".to_string()
}
I wanted to write Some(s: &str). That doesn't work. Is there any way to do that?

I'll be honest, the San Diego Rust meetup is a bit more of a study group at the moment. It's a bit hard to keep the topics both digestible to newbies and neckbeards so we started doing those koan-like exercism-like things to get people off and running faster while letting the more seasoned Rust users being able to give some code review and commentary. It's something I saw from the LA Rust Meetup. Only, they split into two groups and have one be a hack night on their Stockfighter API because their group tends to be larger.

If you have some suggestions, we would be happy to hear them.

# ¿ Aug 22, 2016 03:51

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# ¿ May 5, 2024 09:29

crazysim: May 23, 2004; I AM SOOOOO GAY

Hmm, that reminds me. I should go and check out rustup.rs on Windows. I wonder how well some work Rust CLI utilities will fare in a MinTTY shell.

# ¿ Sep 8, 2016 09:34

crazysim: May 23, 2004; I AM SOOOOO GAY

Sheep posted:

Once docs.rs came back up I was able to get it sorted out in ~30 seconds. Turns out that every mirror of docs.rs is out of date with regard to that crate and I just happened to be unlucky enough to be poking at a recently(?) changed portion of it on the day docs.rs was down.

I will look into rustls though, thanks.

You should run "cargo doc --open". Docs.rs is really convenient but "cargo doc" will generate documentation for the versions of the crates in your project locally and let you "cross-link" the types and stuff as well.

# ¿ Oct 24, 2018 18:06

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