Attribute Macro drop_with_owned_fields 

#[drop_with_owned_fields]

Annotation required on a type in order for DropWithOwnedFields to be implementable for it.

The attribute shall then define a companion struct …ඞFields,

• either as an “anonymous”/“private” (sealed) type, then only nameable through the convenience DestructuredFieldsOf<Self> type alias and naming abstraction layer;

  This is the case when feeding it an attribute arg of as _.

  The following, for instance, fails to compile:

  use ::drop_with_owned_fields::drop_with_owned_fields;
  
  #[drop_with_owned_fields(as _)]
  struct Foo {
      // …
  }
  
  fn main() {
      let _: FooFields; // Error
  }

  with:

  error[E0412]: cannot find type `FooFields` in this scope
    --> src/_lib.rs:114:12
     |
  10 |     let _: FooFields; // Error
     |            ^^^^^^^^^^ not found in this scope
     |

• or, when feeding it an attribute arg of as $($pub:vis)? struct $FooFieldsName:ident, as a properly $FooFieldsName-named, and $pub-visible, type.

  use ::drop_with_owned_fields::drop_with_owned_fields;
  
  #[drop_with_owned_fields(as pub(crate) struct FooFields)]
  pub struct Foo {
      // …
  }
  
  fn main() {
      let _: FooFields; // ✅
  }

See the main crate docs for more info.