Can't compile emplacable-0.1.0-alpha.16

[kouhe3]

error: unconstrained opaque type
   --> C:\Users\X\.cargo\registry\src\mirrors.aliyun.com-0671735e7cc7f5e7\emplacable-0.1.0-alpha.16\src\lib.rs:309:56
    |
309 |     pub type WithEmplacableForFn<'a, T: ?Sized + 'a> = impl EmplacableFn<T> + 'a;
    |                                                        ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: `WithEmplacableForFn` must be used in combination with a concrete type within the same crate

error[E0308]: mismatched types
   --> C:\Users\X\.cargo\registry\src\mirrors.aliyun.com-0671735e7cc7f5e7\emplacable-0.1.0-alpha.16\src\lib.rs:312:9
    |
309 |       pub type WithEmplacableForFn<'a, T: ?Sized + 'a> = impl EmplacableFn<T> + 'a;
    |                                                          ------------------------- the expected opaque type
310 |
311 |       pub fn with_emplacable_closure<T: ?Sized>(val: &mut T) -> WithEmplacableForFn<'_, T> {
    |                                                                 -------------------------- expected `WithEmplacableForFn<'_, T>` because of return type
312 | /         move |emplacer: &mut Emplacer<'_, T>| {
313 | |             let layout = Layout::for_value(val);
314 | |             let metadata = ptr::metadata(val);
...   |
333 | |             });
334 | |         }
    | |_________^ expected opaque type, found closure
    |
    = note: expected opaque type `WithEmplacableForFn<'_, T>`
rustc 1.91.0-nightly (5eda692e7 2025-09-11)