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//@ check-pass
//@ edition:2018
#![feature(ptr_metadata)]
#![feature(type_alias_impl_trait)]
mod opaque {
pub type Opaque = impl std::future::Future;
fn opaque() -> Opaque {
async {}
}
}
fn a<T>() {
// type parameter T is known to be sized
is_thin::<T>();
// tail of ADT (which is a type param) is known to be sized
is_thin::<std::cell::Cell<T>>();
// opaque type is known to be sized
is_thin::<opaque::Opaque>();
}
fn a2<T: Iterator>() {
// associated type is known to be sized
is_thin::<T::Item>();
}
fn is_thin<T: std::ptr::Pointee<Metadata = ()>>() {}
fn main() {}
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