在Rust中实现了Deref 和 DerefMut
就可以使类型表现得像指针一样,可以使用 * 和 .
操作符。下面看一下定义:
trait Deref {
type Target: ?Sized;
fn deref(&self) -> &Self::Target;
}
trait DerefMut: Deref {
fn deref_mut(&mut self) -> &mut Self::Target;
}
下面就简单实现:
use std::ops::DerefMut;
struct Any<T>(T);
impl<T> Any<T> {
fn new(x: T) -> Any<T> {
Any(x)
}
}
impl<T> std::ops::Deref for Any<T> {
type Target = T;
fn deref(&self) -> &T {
&self.0
}
}
impl<T> DerefMut for Any<T> {
fn deref_mut(&mut self) -> &mut T {
&mut self.0
}
}
fn main() {
let mut y = Any::new(1);
*y = 5;
assert_eq!(y.0, 5);
}