我想了解为什么下面的代码片段无法编译。将函数接受为可能具有任何返回类型的函数参数的Go方法是什么？

package main

func main() {
    test(a) // Error: cannot use a (type func() string) as type func() interface {} in argument to test
    test(b) // Error: cannot use b (type func() int) as type func() interface {} in argument to test
}

func a() string {
    return "hello"
}

func b() int {
    return 1
}

func test(x func() interface{}) {

    // some code...
    v := x()
    // some more code....
}

播放：https：//play.golang.org/p/CqbuEZGy12

我的解决方案基于Volker的答案：

package main

import (
    "fmt"
)

func main() {

    // Wrap function a and b with an anonymous function
    // that has an empty interface return type. With this
    // anonymous function, the call signature of test
    // can be satisfied without needing to modify the return
    // type of function a and b.

    test(func() interface{} {
        return a()
    })

    test(func() interface{} {
        return b()
    })
}

func a() string {
     return "hello"
}

func b() int {
    return 1
}

func test(x func() interface{}) {
    v := x()
    fmt.Println(v)  
}

播放：https：//play.golang.org/p/waOGBZZwN7