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// revisions: base extended
//[base] check-fail
//[extended] check-pass
#![feature(generic_associated_types)]
#![cfg_attr(extended, feature(generic_associated_types_extended))]
#![cfg_attr(extended, allow(incomplete_features))]
pub trait FromLendingIterator<A>: Sized {
fn from_iter<T: for<'x> LendingIterator<Item<'x> = A>>(iter: T) -> Self;
}
impl<A> FromLendingIterator<A> for Vec<A> {
fn from_iter<I: for<'x> LendingIterator<Item<'x> = A>>(mut iter: I) -> Self {
//[base]~^ impl has stricter
let mut v = vec![];
while let Some(item) = iter.next() {
v.push(item);
}
v
}
}
pub trait LendingIterator {
type Item<'z>
where
Self: 'z;
fn next(&mut self) -> Option<Self::Item<'_>>;
fn collect<A, B: FromLendingIterator<A>>(self) -> B
where
Self: Sized,
Self: for<'q> LendingIterator<Item<'q> = A>,
{
<B as FromLendingIterator<A>>::from_iter(self)
}
}
fn main() {}
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