rust/tests/ui/needless_range_loop.rs

108 lines
1.9 KiB
Rust

fn calc_idx(i: usize) -> usize {
(i + i + 20) % 4
}
fn main() {
let ns = vec![2, 3, 5, 7];
for i in 3..10 {
println!("{}", ns[i]);
}
for i in 3..10 {
println!("{}", ns[i % 4]);
}
for i in 3..10 {
println!("{}", ns[i % ns.len()]);
}
for i in 3..10 {
println!("{}", ns[calc_idx(i)]);
}
for i in 3..10 {
println!("{}", ns[calc_idx(i) % 4]);
}
let mut ms = vec![1, 2, 3, 4, 5, 6];
for i in 0..ms.len() {
ms[i] *= 2;
}
assert_eq!(ms, vec![2, 4, 6, 8, 10, 12]);
let mut ms = vec![1, 2, 3, 4, 5, 6];
for i in 0..ms.len() {
let x = &mut ms[i];
*x *= 2;
}
assert_eq!(ms, vec![2, 4, 6, 8, 10, 12]);
let g = vec![1, 2, 3, 4, 5, 6];
let glen = g.len();
for i in 0..glen {
let x: u32 = g[i + 1..].iter().sum();
println!("{}", g[i] + x);
}
assert_eq!(g, vec![20, 18, 15, 11, 6, 0]);
let mut g = vec![1, 2, 3, 4, 5, 6];
let glen = g.len();
for i in 0..glen {
g[i] = g[i + 1..].iter().sum();
}
assert_eq!(g, vec![20, 18, 15, 11, 6, 0]);
let x = 5;
let mut vec = vec![0; 9];
for i in x..x + 4 {
vec[i] += 1;
}
let x = 5;
let mut vec = vec![0; 10];
for i in x..=x + 4 {
vec[i] += 1;
}
let arr = [1, 2, 3];
for i in 0..3 {
println!("{}", arr[i]);
}
for i in 0..2 {
println!("{}", arr[i]);
}
for i in 1..3 {
println!("{}", arr[i]);
}
// #2542
for i in 0..vec.len() {
vec[i] = Some(1).unwrap_or_else(|| panic!("error on {}", i));
}
// #3788
let test = Test {
inner: vec![1, 2, 3, 4],
};
for i in 0..2 {
println!("{}", test[i]);
}
}
struct Test {
inner: Vec<usize>,
}
impl std::ops::Index<usize> for Test {
type Output = usize;
fn index(&self, index: usize) -> &Self::Output {
&self.inner[index]
}
}