在方法内部默认情况下会取消对指针的引用吗？

Question

I'm confused by methods on structs in Go. I've following along in a tutorial in which they have:

func (p *Page) save() error {
    filename := p.Title + ".txt"
    return ioutil.WriteFile(filename, p.Body, 0600)
}

From my understanding, p is pointer and you would need to dereference the pointer before retrieving a property for example:

filename := (*p).Title + ".txt"

The only way this makes sense to me is if the dot is acting like -> in C++. What am I missing?

Answer 1

Yes, the pointer to the struct is automatically dereferenced. From the spec on selectors:

The following rules apply to selectors:

1. For a value x of type T or *T where T is not a pointer or interface type, x.f denotes the field or method at the shallowest depth in T where there is such an f. If there is not exactly one f with shallowest depth, the selector expression is illegal.

...

1. As an exception, if the type of x is a named pointer type and (*x).f is a valid selector expression denoting a field (but not a method), x.f is shorthand for (*x).f.

Therefore, the following two statements are the same (with the first being preferred):

filename := p.Title + ".txt"
filename := (*p).Title + ".txt"