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32 lines
936 B
Rust
32 lines
936 B
Rust
use std::mem;
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#[rustfmt::skip]
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#[allow(unused_variables, unused_assignments)]
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fn main() {
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let my_option: Option<()> = None;
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// `unwrap` of an `Option` after checking if it is `None` will panic.
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// Use `if-let` instead.
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if let Some(value) = my_option {
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println!("{value:?}");
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}
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// A comma was missing.
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let my_arr = &[
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-1, -2, -3,
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-4, -5, -6,
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];
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println!("My array! Here it is: {:?}", my_arr);
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let mut my_empty_vec = vec![1, 2, 3, 4, 5];
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// `resize` mutates a vector instead of returning a new one.
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// `resize(0, …)` clears a vector, so it is better to use `clear`.
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my_empty_vec.clear();
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println!("This Vec is empty, see? {my_empty_vec:?}");
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let mut value_a = 45;
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let mut value_b = 66;
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// Use `mem::swap` to correctly swap two values.
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mem::swap(&mut value_a, &mut value_b);
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println!("value a: {}; value b: {}", value_a, value_b);
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}
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