chay.dev
Going through rustlings for the first time
1use std::mem;
2
3#[rustfmt::skip]
4#[allow(unused_variables, unused_assignments)]
5fn main() {
6 let my_option: Option<()> = None;
7 // `unwrap` of an `Option` after checking if it is `None` will panic.
8 // Use `if-let` instead.
9 if let Some(value) = my_option {
10 println!("{value:?}");
11 }
12
13 // A comma was missing.
14 let my_arr = &[
15 -1, -2, -3,
16 -4, -5, -6,
17 ];
18 println!("My array! Here it is: {:?}", my_arr);
19
20 let mut my_empty_vec = vec![1, 2, 3, 4, 5];
21 // `resize` mutates a vector instead of returning a new one.
22 // `resize(0, …)` clears a vector, so it is better to use `clear`.
23 my_empty_vec.clear();
24 println!("This Vec is empty, see? {my_empty_vec:?}");
25
26 let mut value_a = 45;
27 let mut value_b = 66;
28 // Use `mem::swap` to correctly swap two values.
29 mem::swap(&mut value_a, &mut value_b);
30 println!("value a: {}; value b: {}", value_a, value_b);
31}