[go-nuts] implements a interface

I have a question about implements a interface, as below example.



type Comparable interface{
     CompareTo(c Comparable) int
}

type Int int

func (i Int)CompareTo(c Int) int{
     return int(i-c)
}

func main(){
     var i Int
     i = 10
    var c Comparable
     c=i

     fmt.Println(c)
}
Compiler complaint "Int doesn't implement Comparable(Wrong type for
CompareTo method)

And I modified to bellow

type Comparable interface{
     CompareTo(c int) int
}

func (i Int)CompareTo(c int) int{
     return int(i)-c
}


it's work.

I appreciate to anyone who explain this.

Best Regards