func errorProneOperation(n int) error {
	// Create a new Multierror instance, which implements the error interface
	errs := new(valkyrie.MultiError)

	for i := 0; i < n; i++ {
		errs.Push(fmt.Sprintf("error in iteration %d", i))
	}
	// When you have to return an error, call the `HasError` method
	// which returns nil if the length of errors is 0, and returns the errs instance itself if its not
	return errs.HasError()
}

func main() {
	err := errorProneOperation(3)
	if err != nil {
		fmt.Println("err :", err)
	}
	// Outputs:
	// err : error in iteration 0, error in iteration 1, error in iteration 2
	err = errorProneOperation(0)
	if err != nil {
		fmt.Println("err :", err)
	}
	// Does not output anything
}