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I'd like to have a private enum as an implementation detail of my library, but provide a public method (on another type) that returns its kind. However, it seems enum-kinds always copies the visibility of the original enum.

For example:

#[derive(EnumKind)]
#[enum_kind(FooKind)]
enum Foo {
    A(u32),
    B(u64),
}

pub fn get_a_foo() -> FooKind {
    Foo::A(0).into()
}

This produces:

error[E0446]: private type `FooKind` in public interface
  --> src/lib.rs:36:1
   |
29 | #[derive(EnumKind)]
   |          -------- `FooKind` declared as private
...
36 | pub fn get_a_foo() -> FooKind {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can't leak private type

Hi,
thanks for the very handy trait.

Would you consider providing a trait, e.g. something like this:

trait Kind {
    type Kind;
    fn kind() -> Self::Kind
}

This would enable building more generic / reusable code.

For example, in my particular case, I have functions to detect values of duplicated kinds.

Is it possible to use the generated enum in a different crate?

Would it be possible to copy over enum variant documentation to the EnumKind?

It's not a huge issue by any means, but I feel it would make the derived enum feel a little more polished in a public API.

It could even just be an optional behaviour.

I'm getting the following warning when used with cargo clippy:

warning: this lifetime isn't used in the impl
--> src/options.rs:6:39
|
6 | #[derive(Clone, PartialEq, Eq, Debug, EnumKind)]
| ^^^^^^^^
|
= note: #[warn(clippy::extra_unused_lifetimes)] on by default
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#extra_unused_lifetimes
= note: this warning originates in the derive macro EnumKind (in Nightly builds, run with -Z macro-backtrace for more info)

I want to derive Default for my custom enum. To do this, I'd like to write this:

#[derive(EnumKind)]
#[enum_kind(PainterKind, derive(Default))]
pub enum Painter {
	#[default]
	LinePainter,
	CirclePainter,
}

But that #[default] attribute is not on PainterKind, but on Painter. Can we add support for such derives?