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			25 lines
		
	
	
		
			544 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			25 lines
		
	
	
		
			544 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
| // run-pass
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| #![feature(generic_const_exprs)]
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| #![allow(incomplete_features)]
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| 
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| use std::{mem, ptr};
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| 
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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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| 
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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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