从javascripts中的字符串数组中删除重复项[重复]

var arr = ["aa", "bb", "cc", "dd", "bb"];
var res = arr.filter(function(item, index){
  if(arr.lastIndexOf(item) === index){
    return true;
  }
}).sort(function(a, b){
  return a > b;
});
console.log(res);

console.log(_.uniq(["aa", "bb", "cc", "dd", "bb"]));

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