This is a custom derive, using procedural macros, implementation of enum_primitive.

MSRV is 1.34.0

Documentation

https://docs.rs/enum-primitive-derive/

Usage

Add the following to Cargo.toml:

[dependencies] enum-primitive-derive = "^0.1" num-traits = "^0.1"

Then to your code add:

```rust

[macro_use]

extern crate enumprimitivederive; extern crate num_traits;

[derive(Primitive)]

enum Variant { Value = 1, Another = 2, } ```

To be really useful you need use num_traits::FromPrimitive or use num_traits::ToPrimitive or both. You will then be able to use numtraits::FromPrimitive and/or numtraits::ToPrimitive on your enum.

Full Example

```rust

[macro_use]

extern crate enumprimitivederive; extern crate num_traits;

use num_traits::{FromPrimitive, ToPrimitive};

[derive(Primitive)]

enum Foo { Bar = 32, Dead = 42, Beef = 50, }

fn main() { asserteq!(Foo::fromi32(32), Some(Foo::Bar)); asserteq!(Foo::fromi32(42), Some(Foo::Dead)); asserteq!(Foo::fromi64(50), Some(Foo::Beef)); asserteq!(Foo::fromisize(17), None);

let bar = Foo::Bar;
assert_eq!(bar.to_i32(), Some(32));

let dead = Foo::Dead;
assert_eq!(dead.to_isize(), Some(42));

} ```

Complex Example

In this case we attempt to use values created by bindgen.

```rust

[macro_use]

extern crate enumprimitivederive; extern crate num_traits;

use num_traits::{FromPrimitive, ToPrimitive};

pub const ABC: ::std::os::raw::cuint = 1; pub const DEF: ::std::os::raw::cuint = 2; pub const GHI: ::std::os::raw::c_uint = 4;

[derive(Clone, Copy, Debug, Eq, PartialEq, Primitive)]

enum BindGenLike { ABC = ABC as isize, DEF = DEF as isize, GHI = GHI as isize, }

fn main() { asserteq!(BindGenLike::fromisize(4), Some(BindGenLike::GHI)); asserteq!(BindGenLike::fromu32(2), Some(BindGenLike::DEF)); asserteq!(BindGenLike::fromu32(8), None);

let abc = BindGenLike::ABC;
assert_eq!(abc.to_u32(), Some(1));

} ```