41 lines
818 B
Rust
41 lines
818 B
Rust
// Test that we can deduce when projections like `T::Item` outlive the
|
|
// function body. Test that this does not imply that `T: 'a` holds.
|
|
|
|
// compile-flags:-Zverbose
|
|
|
|
use std::cell::Cell;
|
|
|
|
fn twice<F, T>(mut value: T, mut f: F)
|
|
where
|
|
F: FnMut(&T, Cell<&Option<T::Item>>),
|
|
T: Iterator,
|
|
{
|
|
let mut n = value.next();
|
|
f(&value, Cell::new(&n));
|
|
f(&value, Cell::new(&n));
|
|
}
|
|
|
|
fn generic1<T: Iterator>(value: T) {
|
|
// No error here:
|
|
twice(value, |value_ref, item| invoke1(item));
|
|
}
|
|
|
|
fn invoke1<'a, T>(x: Cell<&'a Option<T>>)
|
|
where
|
|
T: 'a,
|
|
{
|
|
}
|
|
|
|
fn generic2<T: Iterator>(value: T) {
|
|
twice(value, |value_ref, item| invoke2(value_ref, item));
|
|
//~^ ERROR the parameter type `T` may not live long enough
|
|
}
|
|
|
|
fn invoke2<'a, T, U>(a: &T, b: Cell<&'a Option<U>>)
|
|
where
|
|
T: 'a,
|
|
{
|
|
}
|
|
|
|
fn main() {}
|