Simple iterator system

main.go

package main

import "fmt"

type KeyChain struct {
	labels 	[]string
	keys 	[]string
	lock    []string
}

func (kc KeyChain) Next(index int) bool {
	// We only need the length of key labels.
	return index < len(kc.labels)
}

func (kc KeyChain) Value(index int) (label, key, lock string) {
	return kc.labels[index], kc.keys[index], kc.lock[index]
}

func main() {
	var keychain = KeyChain{
		labels: []string{"front-door", "backyard", "garage"},
		keys:   []string{"red", "blue", "green"},
		lock:   []string{"big", "simple", "wireless"},
	}

	for f := 0; keychain.Next(f); f++ {
		label, key, lock := keychain.Value(f)

		fmt.Println("Key Label: ", label, "\n    Key: ", key, "\n    Lock: ", lock)
	}
}