GoLang使用Stringer接口为自定义类型重写string方法(byte[4])

    IPAddr
   
    byte[4]
   

    IP地址
   
    {127, 2, 0, 1}
   

    String()
   
    127.2.0.1
   
    [127, 2, 0, 1]
   

package main

import "fmt"

type IPAddr [4]byte

func (p IPAddr) String() string {
   return string(p[0]) + "." + string(p[1]) + "." + string(p[2]) + "." + string(p[3]) // this here does not work. 
   //Even if I simply return p[0] nothing is returned back.
}

func main() {
    a := IPAddr{127, 2, 54, 32}
    fmt.Println("a:", a)
}