Golang flattener experiment

flattener.go

package main

import "fmt"
import "errors"

// Function to flatten nested arrays of integers
// Nested arrays of integers are encoded as arrays of interface{}
func flatten(elements []interface{}) ([]int, error) {

	intarray := []int{}
	var flattenn func(elements []interface{}) error
	flattenn = func(elements []interface{}) error {

		for i := range elements {
			switch elements[i].(type) {
			case int:
				intarray = append(intarray, elements[i].(int))
			case []interface{}:
				slice := elements[i].([]interface{})
				if err := flattenn(slice); err != nil {
					return err
				}
			default:
				return errors.New("Invalid elements argument in flatten")
			}
		}
		return nil
	}

	if err := flattenn(elements); err != nil {
		return nil, err
	} else {
		return intarray, nil
	}
}

// Helper function to create arrays of anything
func bundle(elements ...interface{}) []interface{} {
	return elements
}

func main() {
	elements := bundle(bundle(1, 2, bundle(3)), 4)
	intarray, err := flatten(elements)
	fmt.Println("Error: ", err, " / In: ", elements, " -> Out :", intarray)
}