docs: function computeFactorial(number) {
      number = Number(number);
      if (!(_regex.regex.positiveInteger.test(String(number)) || number === 0)) {
          throw new Error("number should be 0 or positiveNumber but got " + number);
      }
      if (number === 0) {
          return 1;
      }
      var result = 1;
      for (var i = 2; i <= number; i++) {
          result *= i;
      }
      return result;
  }