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// compile-flags:-Zverbose
// Tests closures that propagate an outlives relationship to their
// creator where the subject is a projection with no regions (`<T as
// Iterator>::Item`, to be exact).
#![allow(warnings)]
#![feature(rustc_attrs)]
trait Anything { }
impl<T> Anything for T { }
fn with_signature<'a, T, F>(x: Box<T>, op: F) -> Box<dyn Anything + 'a>
where F: FnOnce(Box<T>) -> Box<dyn Anything + 'a>
{
op(x)
}
#[rustc_regions]
fn no_region<'a, T>(x: Box<T>) -> Box<dyn Anything + 'a>
where
T: Iterator,
{
with_signature(x, |mut y| Box::new(y.next()))
//~^ ERROR the associated type `<T as Iterator>::Item` may not live long enough
}
#[rustc_regions]
fn correct_region<'a, T>(x: Box<T>) -> Box<dyn Anything + 'a>
where
T: 'a + Iterator,
{
with_signature(x, |mut y| Box::new(y.next()))
}
#[rustc_regions]
fn wrong_region<'a, 'b, T>(x: Box<T>) -> Box<dyn Anything + 'a>
where
T: 'b + Iterator,
{
with_signature(x, |mut y| Box::new(y.next()))
//~^ ERROR the associated type `<T as Iterator>::Item` may not live long enough
}
#[rustc_regions]
fn outlives_region<'a, 'b, T>(x: Box<T>) -> Box<dyn Anything + 'a>
where
T: 'b + Iterator,
'b: 'a,
{
with_signature(x, |mut y| Box::new(y.next()))
}
fn main() {}
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