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//@ run-pass
// Test that we can't ignore lifetimes by going through Any.
use std::any::Any;
struct Foo<'a>(&'a str);
fn good(s: &String) -> Foo { Foo(s) }
fn bad1(s: String) -> Option<&'static str> {
let a: Box<dyn Any> = Box::new(good as fn(&String) -> Foo);
a.downcast_ref::<fn(&String) -> Foo<'static>>().map(|f| f(&s).0)
}
trait AsStr<'a, 'b> {
fn get(&'a self) -> &'b str;
}
impl<'a> AsStr<'a, 'a> for String {
fn get(&'a self) -> &'a str { self }
}
fn bad2(s: String) -> Option<&'static str> {
let a: Box<dyn Any> = Box::new(Box::new(s) as Box<dyn for<'a> AsStr<'a, 'a>>);
a.downcast_ref::<Box<dyn for<'a> AsStr<'a, 'static>>>().map(|x| x.get())
}
fn main() {
assert_eq!(bad1(String::from("foo")), None);
assert_eq!(bad2(String::from("bar")), None);
}
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