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#![feature(thin_box)]
// run-pass
use std::boxed::ThinBox;
use std::error::Error;
use std::{fmt, mem};
fn main() {
let thin_error: ThinBox<dyn Error> = ThinBox::new_unsize(Foo);
assert_eq!(mem::size_of::<*const i32>(), mem::size_of_val(&thin_error));
println!("{:?}", thin_error);
let thin = ThinBox::new(42i32);
assert_eq!(mem::size_of::<*const i32>(), mem::size_of_val(&thin));
println!("{:?}", thin);
let thin_slice = ThinBox::<[i32]>::new_unsize([1, 2, 3, 4]);
assert_eq!(mem::size_of::<*const i32>(), mem::size_of_val(&thin_slice));
println!("{:?}", thin_slice);
}
#[derive(Debug)]
struct Foo;
impl fmt::Display for Foo {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "boooo!")
}
}
impl Error for Foo {}
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