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// We used to allow erroneous `DispatchFromDyn` impls whose RHS type contained
// fields that weren't ZSTs. I don't believe this was possible to abuse, but
// it's at least nice to give users better errors.
#![feature(arbitrary_self_types)]
#![feature(unsize)]
#![feature(dispatch_from_dyn)]
use std::marker::Unsize;
use std::ops::DispatchFromDyn;
struct Dispatchable<T: ?Sized, Z> {
_ptr: Box<T>,
z: Z,
}
impl<T, U> DispatchFromDyn<Dispatchable<U, i32>> for Dispatchable<T, ()>
//~^ ERROR implementing `DispatchFromDyn` does not allow multiple fields to be coerced
where
T: Unsize<U> + ?Sized,
U: ?Sized,
{
}
fn main() {}
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