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Cake day: August 2nd, 2023

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  • There’s at least one example you can look at, the Jenkins CI project had code like that (if (name.startsWith("windows 9")) {):

    https://issues.jenkins.io/secure/attachment/18777/PlatformDetail

    Microsoft, for all their faults, do (or at least did) take backwards compatibility very seriously, and the option of “just make devs fix it” would never fly. Here’s a story about how they added special code to Windows 95 to make SimCity’s broken code work on it:

    Windows 95? No problem. Nice new 32 bit API, but it still ran old 16 bit software perfectly. Microsoft obsessed about this, spending a big chunk of change testing every old program they could find with Windows 95. Jon Ross, who wrote the original version of SimCity for Windows 3.x, told me that he accidentally left a bug in SimCity where he read memory that he had just freed. Yep. It worked fine on Windows 3.x, because the memory never went anywhere. Here’s the amazing part: On beta versions of Windows 95, SimCity wasn’t working in testing. Microsoft tracked down the bug and added specific code to Windows 95 that looks for SimCity. If it finds SimCity running, it runs the memory allocator in a special mode that doesn’t free memory right away. That’s the kind of obsession with backward compatibility that made people willing to upgrade to Windows 95.



  • The collect’s in the middle aren’t necessary, neither is splitting by ": ". Here’s a simpler version

    fn main() {
        let text = "seeds: 79 14 55 13\nwhatever";
        let seeds: Vec<_> = text
            .lines()
            .next()
            .unwrap()
            .split_whitespace()
            .skip(1)
            .map(|x| x.parse::<u32>().unwrap())
            .collect();
        println!("seeds: {:?}", seeds);
    }
    

    It is simpler to bang out a [int(num) for num in text.splitlines()[0].split(' ')[1:]] in Python, but that just shows the happy path with no error handling, and does a bunch of allocations that the Rust version doesn’t. You can also get slightly fancier in the Rust version by collecting into a Result for more succinct error handling if you’d like.

    EDIT: Here’s also a version using anyhow for error handling, and the aforementioned Result collecting:

    use anyhow::{anyhow, Result};
    
    fn main() -> Result<()> {
        let text = "seeds: 79 14 55 13\nwhatever";
        let seeds: Vec<u32> = text
            .lines()
            .next()
            .ok_or(anyhow!("No first line!"))?
            .split_whitespace()
            .skip(1)
            .map(str::parse)
            .collect::<Result<_, _>>()?;
        println!("seeds: {:?}", seeds);
        Ok(())
    }