[go interface{}] go interface{} #go #interface

interface.go

// 故意在接口中定义方法, 以防止其他类型无意中实现了该接口
type runtime.Error interface {
	error
    RuntimeError()
}

// or
type testing.TB interface {
	Error(args ...interface{})
	Errorf(format string, args ...interface{})

  	// 私有方法, 这样只有该包下的类型才可以实现该接口
	private()
}

interface1.go

// range over interface{} which stores a slice
package main

import "fmt"
import "reflect"

func main() {
    data := []string{"one","two","three"}
    test(data)
    moredata := []int{1,2,3}
    test(moredata)
}

func test(t interface{}) {
    switch reflect.TypeOf(t).Kind() {
    case reflect.Slice:
        s := reflect.ValueOf(t)

        for i := 0; i < s.Len(); i++ {
            fmt.Println(s.Index(i))
        }
    }
}

// Or, You don't need to use reflection if you know which types to expect.
package main

import "fmt"

func main() {
    loop([]string{"one", "two", "three"})
    loop([]int{1, 2, 3})
}

func loop(t interface{}) {
    switch t := t.(type) {
    case []string:
        for _, value := range t {
            fmt.Println(value)
        }
    case []int:
        for _, value := range t {
            fmt.Println(value)
        }
    }
}