1 // edition:2021 2 // run-pass 3 4 solve<F>(validate: F) -> Option<u64> where F: Fn(&mut [i8; 1]),5fn solve<F>(validate: F) -> Option<u64> 6 where 7 F: Fn(&mut [i8; 1]), 8 { 9 let mut position: [i8; 1] = [1]; 10 Some(0).map(|_| { 11 validate(&mut position); 12 let [_x] = position; 13 0 14 }) 15 } 16 main()17fn main() { 18 solve(|_| ()); 19 } 20