rust/tests/ui/needless_range_loop.rs
2018-10-06 09:43:08 -07:00

66 lines
1.5 KiB
Rust

// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
fn calc_idx(i: usize) -> usize {
(i + i + 20) % 4
}
fn main() {
let ns = [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]);
}