This is completely different from the previous example. It doesn't increment any...

raggi · 2025-12-06T02:18:17 1764987497

    use std::sync::Mutex;
    fn main() -> Result<(), Box<dyn std::error::Error>> {
        static PEDANTRY: Mutex<u64> = Mutex::new(0);
        *PEDANTRY.lock()? += 1;
        println!("{}", PEDANTRY.lock()?);
        Ok(())
    }

hu3 · 2025-12-06T21:36:29 1765056989

Still different. Yours only increments once. Doesn't pass basic QA.

And declaring a static variable inside a function, even if in main, smells.

raggi · 2025-12-06T22:23:41 1765059821

OP you keep comparing to doesn't even declare the variable. I'm done with you.

umanwizard · 2025-12-07T17:31:00 1765128660

OP here, not showing how to declare the variable was an oversight on my part.

  static mut COUNTER: u32 = 0;

(at top-level)

If on 2024 edition, you will additionally need

  #![allow(static_mut_refs)]

raggi · 2025-12-07T18:07:13 1765130833

Yup, your example was fine, as I said I just wanted to show a safe method too :-)