Golang-为什么我可以从值类型调用指针接收器方法？ [重复]

Question

This question already has an answer here:

• Why does a method with a pointer receiver still work when it receives a value? 2 answers

I am going through the Tour of Go again, and I am confused by this Methods Module

In short a type Vertex is specified as well as a function with a pointer receiver

type Vertex struct {
  X, Y float64
}

func (v *Vertex) Scale(f float64) {
  v.X = v.X * f
  v.Y = v.Y * f
}

No worries here. However, my confusion comes from the main function which appears to allow a value type to invoke a method which specifies a pointer receiver.

func main() {
  v := Vertex{3, 4}
  v.Scale(10)
  // v's fields have changed
}

I checked the type of v just to make sure

fmt.Printf("v's type is %T
", v)
// v's type is main.Vertex

Why is this allowed? Shouldn't v need to be a pointer to invoke the Scale method e.g. v := &Vertex{3, 4}

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Answer 1

From the same tutorial, an explanation is provided a few slides later:

In the Methods and pointer indirection slide, the following excerpt provides an explanation:

For the statement v.Scale(10), even though v is a value and not a pointer, the method with the pointer receiver is called automatically. That is, as a convenience, Go interprets the statement v.Scale(10) as (&v).Scale(10) since the Scale method has a pointer receiver.