Golang 如何实现函数的任意类型传参

package main 
import (
	"fmt"
)
 
func init() {
	fmt.Print("init")
}
 
func main() {
	test1("123")
	test1(1)
	test2("123",1, "324", 12)
}
 
// 实现传单个任何类型的参数
 
func test1(v interface{}) {
	fmt.Println(v)                  // 打印 “123” 1
}
 
// 实现传任意多个任意类型的参数
 
func test2(v ...interface{}) {
	for _, m := range v {
		fmt.Println(m)				// 依次打印 123 1 324 12
	}
}

func main() {
    sayhello("john", addperfix)
}
func addperfix(perfix, name string) {
    fmt.Println(perfix, "!", name)
}
func sayhello(name string, f func(string, string)) {
    f("hello", name)
}

func demo(s []interface{}) {
 for _, ele := range s {
  fmt.Println(ele)
 }
}
func Test(t *testing.T) {
 s := []int{1, 2, 3}
 demo(s)
}

func demo(s interface{}) {
 sv := reflect.ValueOf(s)
 svs := sv.Slice(0, sv.Len())
 for i := 0; i < svs.Len(); i++ {
  e := svs.Index(i).Interface()
  switch e.(type) {
  case string:
   fmt.Println("string", e)
  case int:
   fmt.Println("int", e)
  }
 }
}
func Test(t *testing.T) {
 s1 := []int{1, 2, 3}
 demo(s1)
 s2 := []string{"a", "b", "c"}
 demo(s2)
}