/*补充代码*/

      let x = 10; 

      let y = 20;

      let z = 30;

      [x, y, z] = [z, x, y];

      console.log(x, y, z);

VM2058:1 Uncaught SyntaxError: Identifier 'x' has already been declared

    at <anonymous>:1:1

    at n.runCode (code.js?v=202101081807:1)

    at Array.<anonymous> (code.js?v=202101081807:1)

    at b.r._signal (ace.js?v=202101081807:1)

    at b.onDocumentChange (ace.js?v=202101081807:1)

    at p.r._signal (ace.js?v=202101081807:1)

    at p.onChange (ace.js?v=202101081807:1)

    at a.r._signal (ace.js?v=202101081807:1)

    at applyDelta (ace.js?v=202101081807:1)

    at a.remove (ace.js?v=202101081807:1)

​