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// run-pass
#![feature(associated_type_bounds)]
#![allow(unused_assignments)]
trait Tr1: Copy { type As1: Copy; }
trait Tr2: Copy { type As2: Copy; }
trait Tr3: Copy { type As3: Copy; }
trait Tr4<'a>: Copy { type As4: Copy; }
trait Tr5: Copy { type As5: Copy; }
impl Tr1 for &str { type As1 = bool; }
impl Tr2 for bool { type As2 = u8; }
impl Tr3 for u8 { type As3 = fn() -> u8; }
impl Tr1 for () { type As1 = (usize,); }
impl<'a> Tr4<'a> for (usize,) { type As4 = u8; }
impl Tr5 for bool { type As5 = u16; }
union Un1<T: Tr1<As1: Tr2>> {
outest: T,
outer: T::As1,
inner: <T::As1 as Tr2>::As2,
}
union Un2<T: Tr1<As1: Tr2<As2: Tr3>>> {
outest: T,
outer: T::As1,
inner: <T::As1 as Tr2>::As2,
}
union Un3<T: Tr1<As1: 'static>> {
outest: T,
outer: &'static T::As1,
}
union Un4<'x1, 'x2, T: Tr1<As1: for<'l> Tr4<'l>>> {
f1: &'x1 <T::As1 as Tr4<'x1>>::As4,
f2: &'x2 <T::As1 as Tr4<'x2>>::As4,
}
union _Un5<'x1, 'x2, T: Tr1<As1: for<'l> Tr4<'l, As4: Copy>>> {
f1: &'x1 <T::As1 as Tr4<'x1>>::As4,
f2: &'x2 <T::As1 as Tr4<'x2>>::As4,
}
union Un6<T>
where
T: Tr1<As1: Tr2 + 'static + Tr5>,
{
f0: T,
f1: <T::As1 as Tr2>::As2,
f2: &'static T::As1,
f3: <T::As1 as Tr5>::As5,
}
union _Un7<'a, 'b, T> // `<T::As1 as Tr2>::As2: 'a` is implied.
where
T: Tr1<As1: Tr2>,
{
f0: &'a T,
f1: &'b <T::As1 as Tr2>::As2,
}
unsafe fn _use_un7<'a, 'b, T>(x: _Un7<'a, 'b, T>)
where
T: Tr1,
T::As1: Tr2,
{
let _: &'a T = &x.f0;
}
#[derive(Copy, Clone)]
union UnSelf<T> where Self: Tr1<As1: Tr2>, T: Copy {
f0: T,
f1: <Self as Tr1>::As1,
f2: <<Self as Tr1>::As1 as Tr2>::As2,
}
impl Tr1 for UnSelf<&'static str> { type As1 = bool; }
fn main() {
let mut un1 = Un1 { outest: "foo" };
un1 = Un1 { outer: true };
assert_eq!(unsafe { un1.outer }, true);
un1 = Un1 { inner: 42u8 };
assert_eq!(unsafe { un1.inner }, 42u8);
let mut un2 = Un2 { outest: "bar" };
assert_eq!(unsafe { un2.outest }, "bar");
un2 = Un2 { outer: true };
assert_eq!(unsafe { un2.outer }, true);
un2 = Un2 { inner: 42u8 };
assert_eq!(unsafe { un2.inner }, 42u8);
let mut un3 = Un3 { outest: "baz" };
assert_eq!(unsafe { un3.outest }, "baz");
un3 = Un3 { outer: &true };
assert_eq!(unsafe { *un3.outer }, true);
let f1 = (1,);
let f2 = (2,);
let mut un4 = Un4::<()> { f1: &f1.0 };
assert_eq!(1, unsafe { *un4.f1 });
un4 = Un4 { f2: &f2.0 };
assert_eq!(2, unsafe { *un4.f2 });
let mut un6 = Un6 { f0: "bar" };
assert_eq!(unsafe { un6.f0 }, "bar");
un6 = Un6 { f1: 24u8 };
assert_eq!(unsafe { un6.f1 }, 24u8);
un6 = Un6 { f2: &true };
assert_eq!(unsafe { un6.f2 }, &true);
un6 = Un6 { f3: 12u16 };
assert_eq!(unsafe { un6.f3 }, 12u16);
let mut unself = UnSelf::<_> { f0: "selfish" };
assert_eq!(unsafe { unself.f0 }, "selfish");
unself = UnSelf { f1: true };
assert_eq!(unsafe { unself.f1 }, true);
unself = UnSelf { f2: 24u8 };
assert_eq!(unsafe { unself.f2 }, 24u8);
}
|
