mirror of https://github.com/rust-lang/rust
25 lines
545 B
Rust
25 lines
545 B
Rust
//@ run-pass
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#![feature(generic_const_exprs)]
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#![allow(incomplete_features)]
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use std::{mem, ptr};
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fn split_first<T, const N: usize>(arr: [T; N]) -> (T, [T; N - 1])
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where
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[T; N - 1]: Sized,
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{
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let arr = mem::ManuallyDrop::new(arr);
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unsafe {
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let head = ptr::read(&arr[0]);
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let tail = ptr::read(&arr[1..] as *const [T] as *const [T; N - 1]);
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(head, tail)
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}
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}
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fn main() {
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let arr = [0, 1, 2, 3, 4];
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let (head, tail) = split_first(arr);
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assert_eq!(head, 0);
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assert_eq!(tail, [1, 2, 3, 4]);
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}
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