package main

import (
    "reflect"
    "fmt"
)

type Test struct {
    fn interface{}
    args []reflect.Value
}

func foo(t Test) {
    reflect.ValueOf(t.fn).Call(t.args)
}

func bar(i, j int) {
    fmt.Println(i+j)
}

func main() {
    f := bar
    x, y := 3, 5
    arg := []reflect.Value{reflect.ValueOf(x), reflect.ValueOf(y)}
    test := Test{
        fn:  f,
        args: arg,
    }

    foo(test)
}