数组去重

判断obj对象是否在arr数组里面，是返回true

const dealArray = (arr, obj) => {
  Array.prototype.S = String.fromCharCode(2);
  Array.prototype.in_array = function (e) {
    var r = new RegExp(this.S + e + this.S);
    return (r.test(this.S + this.join(this.S) + this.S));
  };
  return (arr.in_array(obj))
}

来源：https://www.cnblogs.com/wwj007/p/11851526.html