package main import "fmt" type IPAddr [4]byte func (i IPAddr) String() string { return fmt.Sprintf("\"%d.%d.%d.%d\"", i[0], i[1], i[2], i[3]) } func main() { hosts := map[string]IPAddr{ "loopback": {127, 0, 0, 1}, "googleDNS": {8, 8, 8, 8}, } for name, ip := range hosts { fmt.Printf("%v: %v\n", name, ip) } }