flatten.go

flatten.go

package main

// RUN IT! https://play.golang.org/p/hUrvvq_gBQX

import (
	"fmt"
)

func flatten(iface interface{}) []int {

	flattened := make([]int, 0)

	type flattener func(interface{})
	var recursiveFlatten flattener

	recursiveFlatten = func(sublist interface{}) {
		if theList, listOK := sublist.([]interface{}); listOK {
			for i := 0; i < len(theList); i++ {
				theInt, intOK := theList[i].(int)
				if intOK {
					flattened = append(flattened, theInt)
				} else {
					recursiveFlatten(theList[i])
				}
			}
		}
	}

	recursiveFlatten(iface)

	return flattened
}

func main() {

	var one interface{} = 1
	var two interface{} = 2
	var three interface{} = 3
	var four interface{} = 4
	var five interface{} = 5
	var six interface{} = 6

	list := make([]interface{}, 0)
	list = append(list, one)
	list = append(list, two)
	sublist0 := make([]interface{}, 0)
	sublist0 = append(sublist0, three)
	sublist1 := make([]interface{}, 0)
	sublist1 = append(sublist1, five)
	sublist1 = append(sublist1, six)
	sublist0 = append(sublist0, sublist1)
	sublist0 = append(sublist0, four)
	list = append(list, sublist0)

	fmt.Printf("%v\n", list)
	fmt.Printf("%v\n", flatten(list))
}