exercise-stringer.go

package main

import (
	"fmt"
	"strings"
	)

type IPAddr [4]byte

func (p IPAddr) String() string {
	var v []string
	for i := range p {
		byte := p[i]
		s := fmt.Sprintf("%v", byte)
		v = append(v, s)
	}
	return fmt.Sprintf("%v", strings.Join(v[:],"."))
}


// TODO: Add a "String() string" method to IPAddr.

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)
	}
}

https://tour.go-zh.org/methods/18