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//@ run-pass
#![feature(derive_coerce_pointee, arbitrary_self_types)]
use std::marker::CoercePointee;
#[derive(CoercePointee)]
#[repr(transparent)]
struct MyPointer<'a, #[pointee] T: ?Sized> {
ptr: &'a T,
}
impl<T: ?Sized> Copy for MyPointer<'_, T> {}
impl<T: ?Sized> Clone for MyPointer<'_, T> {
fn clone(&self) -> Self {
Self { ptr: self.ptr }
}
}
impl<'a, T: ?Sized> core::ops::Deref for MyPointer<'a, T> {
type Target = T;
fn deref(&self) -> &'a T {
self.ptr
}
}
struct MyValue(u32);
impl MyValue {
fn through_pointer(self: MyPointer<'_, Self>) -> u32 {
self.ptr.0
}
}
trait MyTrait {
fn through_trait(&self) -> u32;
fn through_trait_and_pointer(self: MyPointer<'_, Self>) -> u32;
}
impl MyTrait for MyValue {
fn through_trait(&self) -> u32 {
self.0
}
fn through_trait_and_pointer(self: MyPointer<'_, Self>) -> u32 {
self.ptr.0
}
}
pub fn main() {
let v = MyValue(10);
let ptr = MyPointer { ptr: &v };
assert_eq!(v.0, ptr.through_pointer());
assert_eq!(v.0, ptr.through_pointer());
let dptr = ptr as MyPointer<dyn MyTrait>;
assert_eq!(v.0, dptr.through_trait());
assert_eq!(v.0, dptr.through_trait_and_pointer());
}
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