# enum-kinds

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Custom derive for generating enums with matching variants but without any of
the data.

In other words, `enum-kinds` automatically generates enums that have the same
set of variants as the original enum, but with all the embedded data stripped
away (that is, all the variants of the newly-generated enum are unit variants).
Additionally, `enum-kinds` implements `From` trait for going from the original
enum to the unit variant version.

The crate is compatible with stable Rust releases. This crate replaces
earlier `enum_kinds_macros` and `enum_kinds_traits` crates.

# Example

```rust,ignore
#[macro_use]
extern crate enum_kinds;

#[derive(EnumKind)]
#[enum_kind(SomeEnumKind)]
enum SomeEnum {
    First(String, u32),
    Second(char),
    Third
}

#[test]
fn test_enum_kind() {
    let first = SomeEnum::First("Example".to_owned(), 32);
    assert_eq!(SomeEnumKind::from(&first), SomeEnumKind::First);
}
```

The `#[derive(EnumKind)]` attribute automatically creates another `enum` named
`SomeEnumKind` that contains matching unit variant for each of the variants in
`SomeEnum`.

# Additional Attributes for Generated Enums

By default, derived kind enums implement `Debug`, `Clone`, `Copy`, `PartialEq`
and `Eq` traits. Additional attributes can be attached to the generated `enum`
by including them to the `enum_kind` attribute: `#[enum_kind(NAME,
derive(SomeTrait), derive(AnotherTrait))]`. For example, to implement
[Serde's](https://serde.rs) Serialize and Deserialize traits:

``` rust,ignore
#[macro_use]
extern crate enum_kinds;

#[macro_use]
extern crate serde_derive;
extern crate serde;

#[derive(EnumKind)]
#[enum_kind(AdditionalDerivesKind, derive(Serialize, Deserialize))]
enum AdditionalDerives {
    Variant(String, u32),
    Another(String)
}
```

# no_std support

`enum-kinds` can be used without the standard library by enabling `no-stdlib`
feature.

# Issues

If you encounter any problems using the crate, please report them at [the issue
tracker](https://github.com/Soft/enum-kinds/issues).

# License

The crate is available under the terms of [MIT license](https://opensource.org/licenses/MIT).