Rust❤️ increment(++) decrement(--)하는 법

https://www.reddit.com/r/rust/comments/jf66eu/why_are_there_no_increment_and_decrement/

Why are there no increment (++) and decrement (--) operators in Rust?

increment(++)

for i in 0..1000 {
    println!("{:?}", i);
}

decrement(--)하는 법

for i in (0..1000).rev() {
    println!("{:?}", i);
}

예시

use rayon::prelude::*;
use std::time::{Duration, Instant};

fn increment_all(input: &mut [i32]) {
    input.par_iter_mut().for_each(|p| *p += 1);
        for i in (0..1000).rev() {
            println!("{:?}", i);
    }
}

fn main() {
    let now_1 = Instant::now();
    let now_2 = Instant::now();
    print!("thread1 : ");
    print!("{:?}", increment_all(&mut [10]));
    let elapsed1= now_1.elapsed().as_millis();

    print!("thread2 : ");
    print!("{:?}", increment_all(&mut [10]));
    let elapsed2 = now_2.elapsed().as_millis();
     
    
    println!("1nd thread elapse : {elapsed1} millsec");
    println!("2nd thread elapse : {elapsed2} millsec");
}

결과

2
1
0
()1nd thread elapse : 10 millsec
2nd thread elapse : 10 millsec

https://stackoverflow.com/questions/25170091/how-to-make-a-reverse-ordered-for-loop

How to make a reverse ordered for loop?

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