Permute array and return array of permutations

Permute

var temp = [];
      var answer = [];

      return doIt(arr);

      function doIt(a) {
        var i, len, item;

        for (i = 0, len = arr.length; i < len; i++) {
          // remove the item at index i
          console.log(i);
          
          item = arr.splice(i, 1)[0];

          // add that item to the array we're building up
          temp.push(item);

          if (arr.length) {
            // if there's still anything left in the array,
            // recurse over what's left
            doIt(arr);
          } else {
            // otherwise, log the result and move on
            logResult();
          }

          // restore the item we removed at index i
          // and remove it from our temp array
          arr.splice(i, 0, item);
          temp.pop();
        }

        return answer;
      }

      function logResult() {
        answer.push(
          // make a copy of temp using .slice()
          // so we can continue to work with temp
          temp.slice()
        );  
        
      }