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// run-pass
#![feature(associated_type_bounds)]
use std::ops::Add;
trait Tr1 { type As1; fn mk(self) -> Self::As1; }
trait Tr2<'a> { fn tr2(self) -> &'a Self; }
fn assert_copy<T: Copy>(x: T) { let _x = x; let _x = x; }
fn assert_static<T: 'static>(_: T) {}
fn assert_forall_tr2<T: for<'a> Tr2<'a>>(_: T) {}
struct S1;
#[derive(Copy, Clone)]
struct S2;
impl Tr1 for S1 { type As1 = S2; fn mk(self) -> Self::As1 { S2 } }
fn def_et1() -> impl Tr1<As1: Copy> { S1 }
pub fn use_et1() { assert_copy(def_et1().mk()); }
fn def_et2() -> impl Tr1<As1: 'static> { S1 }
pub fn use_et2() { assert_static(def_et2().mk()); }
fn def_et3() -> impl Tr1<As1: Clone + Iterator<Item: Add<u8, Output: Into<u8>>>> {
struct A;
impl Tr1 for A {
type As1 = core::ops::Range<u8>;
fn mk(self) -> Self::As1 { 0..10 }
}
A
}
pub fn use_et3() {
let _0 = def_et3().mk().clone();
let mut s = 0u8;
for _1 in _0 {
let _2 = _1 + 1u8;
s += _2.into();
}
assert_eq!(s, (0..10).map(|x| x + 1).sum());
}
fn def_et4() -> impl Tr1<As1: for<'a> Tr2<'a>> {
#[derive(Copy, Clone)]
struct A;
impl Tr1 for A {
type As1 = A;
fn mk(self) -> A { A }
}
impl<'a> Tr2<'a> for A {
fn tr2(self) -> &'a Self { &A }
}
A
}
pub fn use_et4() { assert_forall_tr2(def_et4().mk()); }
fn main() {
let _ = use_et1();
let _ = use_et2();
let _ = use_et3();
let _ = use_et4();
}
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