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// run-pass
#![allow(dead_code)]
use std::rc::Rc;
use std::ops::Deref;
#[derive(Copy, Clone)]
struct DerefWrapper<X, Y> {
x: X,
y: Y
}
impl<X, Y> DerefWrapper<X, Y> {
fn get_x(self) -> X {
self.x
}
}
impl<X, Y> Deref for DerefWrapper<X, Y> {
type Target = Y;
fn deref(&self) -> &Y {
&self.y
}
}
mod priv_test {
use std::ops::Deref;
#[derive(Copy, Clone)]
pub struct DerefWrapperHideX<X, Y> {
x: X,
pub y: Y
}
impl<X, Y> DerefWrapperHideX<X, Y> {
pub fn new(x: X, y: Y) -> DerefWrapperHideX<X, Y> {
DerefWrapperHideX {
x: x,
y: y
}
}
}
impl<X, Y> Deref for DerefWrapperHideX<X, Y> {
type Target = Y;
fn deref(&self) -> &Y {
&self.y
}
}
}
pub fn main() {
let nested = DerefWrapper {x: true, y: DerefWrapper {x: 0, y: 1}};
// Use the first field that you can find.
assert_eq!(nested.x, true);
assert_eq!((*nested).x, 0);
// Same for methods, even though there are multiple
// candidates (at different nesting levels).
assert_eq!(nested.get_x(), true);
assert_eq!((*nested).get_x(), 0);
// Also go through multiple levels of indirection.
assert_eq!(Rc::new(nested).x, true);
let nested_priv = priv_test::DerefWrapperHideX::new(true, DerefWrapper {x: 0, y: 1});
assert_eq!(nested_priv.x, 0);
assert_eq!((*nested_priv).x, 0);
}
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