Comment by sunnyps

Would the interface nil example be clearer if checking for `nil` didn't use the `==` operator? For example, with a hypothetical `is` operator:

    package main
    import "fmt"
    type I interface{}
    type S struct{}
    func main() {
        var i I
        var s *S
        fmt.Println(s, i) // nil nil
        fmt.Println(s is nil, i is nil, s == i) // t,t,f: Not confusing anymore?
        i = s
        fmt.Println(s, i) // nil nil
        fmt.Println(s is nil, i is nil, s == i) // t,f,t: Still not confusing?
    }

Of course, this means you have to precisely define the semantics of `is` and `==`:

- `is` for interfaces checks both value and interface type.

- `==` for interfaces uses only the value and not the interface type.

- For structs/value, `is` and `==` are obvious since there's only a value to check.