function Compare$1(params) {
    Operator.call(this, null, update$5, params);
  }
Generates a comparator function.
@constructor
@param {object} params - The parameters for this operator.
@param {Array<string|function>} params.fields - The fields to compare.
@param {Array<string>} [params.orders] - The sort orders.
  Each entry should be one of "ascending" (default) or "descending".