Rust Notes - 01

普通的數組數據交換，

    let mut val = [1,2,3];

    let t = val[0];
    val[0] = val[1];
    val[1] = t;

it works...下面的也work：

    let mut val = ["1","2","3"];

    let t = val[0];
    val[0] = val[1];
    val[1] = t;

但，

   let mut val = ["1".to_string(),"2".to_string(),"3".to_string()];
   
    let t = val[0];
    val[0] = val[1];
    val[1] = t;

編譯出錯：

<anon>:32:13: 32:19 error: cannot move out of type `[collections::string::String; 3]`, a non-copy fixed-size array <anon>:32 let t = val[0]; ^~~~~~ <anon>:32:9: 32:10 note: attempting to move value to here <anon>:32 let t = val[0]; ^ <anon>:32:9: 32:10 help: to prevent the move, use `ref t` or `ref mut t` to capture value by reference <anon>:33:14: 33:20 error: cannot move out of type `[collections::string::String; 3]`, a non-copy fixed-size array <anon>:33 val[0] = val[1]; ^~~~~~ error: aborting due to 2 previous errors

  正確的交換方式是，

    val.swap(0,1);