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// run-pass
#![allow(unused)]
#![feature(associated_type_bounds)]
trait Tr1 { type As1; }
trait Tr2 { type As2; }
trait Tr3 {}
trait Tr4<'a> { type As4; }
trait Tr5 { type As5; }
impl Tr1 for &str { type As1 = bool; }
impl Tr2 for bool { type As2 = u8; }
impl Tr3 for u8 {}
impl Tr1 for () { type As1 = (usize,); }
impl<'a> Tr4<'a> for (usize,) { type As4 = u8; }
impl Tr5 for bool { type As5 = u16; }
struct St1<T: Tr1<As1: Tr2>> {
outest: T,
outer: T::As1,
inner: <T::As1 as Tr2>::As2,
}
fn unwrap_1_st1<T: Tr1<As1: Tr2>>(x: St1<T>) -> (T, T::As1, <T::As1 as Tr2>::As2) {
(x.outest, x.outer, x.inner)
}
fn unwrap_2_st1<T>(x: St1<T>) -> (T, T::As1, <T::As1 as Tr2>::As2)
where
T: Tr1,
T::As1: Tr2,
{
unwrap_1_st1(x)
}
struct St2<T: Tr1<As1: Tr2<As2: Tr3>>> {
outest: T,
outer: T::As1,
inner: <T::As1 as Tr2>::As2,
}
struct St3<T: Tr1<As1: 'static>> {
outest: T,
outer: &'static T::As1,
}
struct St4<'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,
}
struct St5<'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,
}
struct St6<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,
}
struct St7<'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,
}
fn _use_st7<'a, 'b, T>(x: St7<'a, 'b, T>)
where
T: Tr1,
T::As1: Tr2,
{
let _: &'a T = &x.f0;
}
struct StSelf<T> where Self: Tr1<As1: Tr2> {
f2: <<Self as Tr1>::As1 as Tr2>::As2,
}
impl Tr1 for StSelf<&'static str> { type As1 = bool; }
fn main() {
let st1 = St1 { outest: "foo", outer: true, inner: 42u8 };
assert_eq!(("foo", true, 42), unwrap_1_st1(st1));
let _ = St2 { outest: "foo", outer: true, inner: 42u8 };
let _ = St3 { outest: "foo", outer: &true };
let f1 = (1,);
let f2 = (2,);
let st4 = St4::<()> { f1: &f1.0, f2: &f2.0, };
assert_eq!((&1, &2), (st4.f1, st4.f2));
// FIXME: requires lazy normalization.
/*
let f1 = (1,);
let f2 = (2,);
let st5 = St5::<()> { f1: &f1.0, f2: &f2.0, };
assert_eq!((&1, &2), (st5.f1, st5.f2));
*/
let st6 = St6 { f0: "bar", f1: 24u8, f2: &true, f3: 12u16, };
assert_eq!(("bar", 24, &true, 12), (st6.f0, st6.f1, st6.f2, st6.f3));
let stself = StSelf::<&'static str> { f2: 42u8 };
assert_eq!(stself.f2, 42u8);
}
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