| // Copyright 2014 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| |
| 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}); |
| // FIXME(eddyb) #12808 should skip private fields. |
| // assert_eq!(nested_priv.x, 0); |
| assert_eq!((*nested_priv).x, 0); |
| } |