正如标题所述，为什么下面的代码可以编译？

use std::ops::Deref;

struct Foo {}

fn main() {
    let b = Box::new(Foo{});
    
    let pb = *b; //works
    // let pb = *b.deref();  // error[E0507]: cannot move out of a shared reference
}

对于具有非Copy目标的自定义类型，情况并非如此。

use std::ops::Deref;

struct Foo<T> {
    p: T,
}

impl<T> Deref for Foo<T> {
    type Target = T;

    fn deref(&self) -> &<Self as Deref>::Target {
        &self.p
    }
}

fn main() {
    let f = Foo { p: vec![1u8] };

    let pf = *f; // error[E0507]: cannot move out of a shared reference
    let pf = *f.deref(); // error[E0507]: cannot move out of a shared reference
}

*Box不是在做*Box.deref()吗？