go - Type func with interface parameter incompatible error

Question

I have declared a new type func that takes any value that conforms to interface{}. However, when I invoke a function that has been passed as an argument (conforming to that type specification) I get an error.

Can somebody explain why this is the case? Below is the simplest example I could recreate the issue with.

type myfunc func(x interface{})

func a(num int) {
    return
}

func b(f myfunc) {
    f(2)
    return
}

func main() {
    b(a) // error: cannot use a (type func(int)) as type myfunc in argument to b
    return
}

Answer 1

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