Go方法调用速记规范适用性

Question

From the Calls section of Go spec: https://golang.org/ref/spec#Calls

A method call x.m() is valid if the method set of (the type of) x contains m and the argument list can be assigned to the parameter list of m. If x is addressable and &x's method set contains m, x.m() is shorthand for (&x).m()

My program.

package main

import (
    "fmt"
)

func main() {
    p := Point{2, 3}

    p.FakeScale(10)
    fmt.Println(p)

    p.RealScale(10)
    fmt.Println(p)
}

type Point struct {
    x int
    y int
}

func (p Point) FakeScale(s int) {
    p.x *= s
    p.y *= s
}

func (p *Point) RealScale(s int) {
    p.x *= s
    p.y *= s
}

Here is the output.

{2, 3}
{20, 30}

My question is specifically about this part of the spec.

If x is addressable and &x's method set contains m, x.m() is shorthand for (&x).m()

My questions.

1. Is the quoted part applicable to p.FakeScale(10)? My guess is "No" because although p is addressable, &p's method set does not contain FakeScale. p's method set contains FakeScale because it uses value receiver, but p's method set does not contain FakeScale, therefore this part of the spec is not applicable to p.FakeScale(10). Am I correct?
2. Is the quoted part applicable to p.RealScale(10)? My guess is "Yes" because p is addressable and &p's method set contains RealScale by virtue of it using a pointer receiver. Therefore, this part of the spec is applicable to p.RealScale(10). Am I correct?
3. Can you provide an example code where x.m() is valid but x is not addressable, and thus this part of the spec is not applicable?

Answer 1

Hm. Also I begin to doubt my knowledge of English language but I will try to answer.

You quoted 2 sentences from specification.

1. Describes conditions for method to be valid.
2. Describes shorthand for recievers of pointer types.

Back to your question:

You defined 2 methods for 2 types: first - reciever of Point and second - receiver of pointer to Point.

Obviously, shorthand definition for pointer types is not applicable for non-pointer types.

So, you're correct in your questions 1 or 2.

And your third question is in fact question 1: FakeScale is valid method but method with non-pointer type in receiver, so shorthand definition is not applicable.