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#![feature(thin_box)]
//@ run-pass
use std::boxed::ThinBox;
use std::error::Error;
use std::ops::Deref;
use std::fmt;
fn main() {
let expected = "Foo error!";
let a: ThinBox<dyn Error> = ThinBox::new_unsize(Foo(expected));
let a = a.deref();
let msg = a.to_string();
assert_eq!(expected, msg);
}
#[derive(Debug)]
#[repr(align(1024))]
struct Foo(&'static str);
impl fmt::Display for Foo {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{}", self.0)
}
}
impl Error for Foo {}
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