函数接受接口时向字符串传递指针?

正如你在笔记中所说,我很确定这不必这么复杂,但要在你的环境中发挥作用:

package main

import (
    "fmt"
    "reflect"
)

type HeadInterface interface {
    Head(interface{})
}

func Head(slice HeadInterface, result interface{}) {
    slice.Head(result)
}

type StringSlice []string

func (slice StringSlice) Head(result interface{}) {
    switch result := result.(type) {
    case *string:
        *result = reflect.ValueOf(slice[0]).String()
        fmt.Println("inside Head:", *result)
    default:
        panic("can't handle this type!")
    }

}

func main() {
    test := StringSlice{"Phil", "Jessica", "Andrea"}

    // empty result string for population within the function
    var result string = ""

    // Calling the function (it is a call to 'x.Head' because I lazily just called th import 'x')
    Head(test, &result)

    // I would have thought I would have gotten "Phil" here, but instead, it is still empty, despite the Println in the function, calling it "phil.
    fmt.Println("outside:", result)
}