问JavaScript:是否删除数组中所有重复的元素？

EN

var nums = [1, 2, 3, 4, 5, 1, 2, 3];

var noDupes = nums.slice().sort()  //sort it so numbers line up
  .reduce(function(result, c, i, arr){  //loop over the set
  if (c !== arr[i+1] && c !== arr[i-1]) { //see if number is before or after
    result.push(c) //if not, than add it
  }
  return result
}, [])

console.log(noDupes);


var noDupes2 = nums.slice().sort()  
  .filter((c, i, arr) => c !== arr[i+1] && c !== arr[i-1])

console.log(noDupes2);

var nums = [1, 2, 3, 4, 5, 1, 2, 3];

var noDupes = nums.filter(( c, i, arr) => arr.indexOf(c) === arr.lastIndexOf(c))
console.log(noDupes)

a = [1, 2, 3, 4, 5, 1, 2, 3];
//console.log(a);
b = a.filter((value) => a.indexOf(value) == a.lastIndexOf(value));
console.log(b)