rust - How to easily copy a non-mut &[u8] into to a &mut [u8] -

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i want manipulations on &mut [u8].

in testing code have:

#[test] fn test_swap_bytes() {     let input: &[u8] = b"abcdef";     let result: &mut[u8] = ?;     do_something(result);     assert_eq!(b"fedcba", result); }

how can mutable u8 slice in case? should put on place of question mark?

you can use fact binary literal knows size @ compile-time. therefor can dereference , store on stack. let binding can mutable let binding.

let mut input: [u8; 6] = *b"abcdef";

see playpen working example

note there's no reason specify type, showed clarity.


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