【GO】go泛型声明的一个疑问？

表示一个类型的集合，这个集合里只有一个类型，就是 *int。

Interface Type

// An interface representing only the type int.
interface {
    int
}

// An interface representing all types with underlying type int.
interface {
    ~int
}

// An interface representing all types with underlying type int that implement the String method.
interface {
    ~int
    String() string
}

// An interface representing an empty type set: there is no type that is both an int and a string.
interface {
    int
    string
}