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+[![Build status](https://gitlab.com/cardoe/enum-primitive-derive/badges/master/pipeline.svg)](https://gitlab.com/cardoe/enum-primitive-derive/commits/master)
+[![Rust version]( https://img.shields.io/badge/rust-1.34+-blue.svg)]()
+[![Documentation](https://docs.rs/enum-primitive-derive/badge.svg)](https://docs.rs/enum-primitive-derive)
+[![Latest version](https://img.shields.io/crates/v/enum-primitive-derive.svg)](https://crates.io/crates/enum-primitive-derive)
+[![All downloads](https://img.shields.io/crates/d/enum-primitive-derive.svg)](https://crates.io/crates/enum-primitive-derive)
+[![Downloads of latest version](https://img.shields.io/crates/dv/enum-primitive-derive.svg)](https://crates.io/crates/enum-primitive-derive)
+
+This is a custom derive, using procedural macros, implementation of
+[enum_primitive](https://crates.io/crates/enum_primitive).
+
+MSRV is 1.34.0
+
+## Documentation
+
+[https://docs.rs/enum-primitive-derive/](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 enum_primitive_derive;
+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
+[num_traits::FromPrimitive](https://rust-num.github.io/num/num/trait.FromPrimitive.html)
+and/or
+[num_traits::ToPrimitive](https://rust-num.github.io/num/num/trait.ToPrimitive.html)
+on your enum.
+
+## Full Example
+
+```rust
+#[macro_use]
+extern crate enum_primitive_derive;
+extern crate num_traits;
+
+use num_traits::{FromPrimitive, ToPrimitive};
+
+#[derive(Primitive)]
+enum Foo {
+    Bar = 32,
+    Dead = 42,
+    Beef = 50,
+}
+
+fn main() {
+    assert_eq!(Foo::from_i32(32), Some(Foo::Bar));
+    assert_eq!(Foo::from_i32(42), Some(Foo::Dead));
+    assert_eq!(Foo::from_i64(50), Some(Foo::Beef));
+    assert_eq!(Foo::from_isize(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](https://crates.io/crates/bindgen).
+
+```rust
+#[macro_use]
+extern crate enum_primitive_derive;
+extern crate num_traits;
+
+use num_traits::{FromPrimitive, ToPrimitive};
+
+pub const ABC: ::std::os::raw::c_uint = 1;
+pub const DEF: ::std::os::raw::c_uint = 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() {
+    assert_eq!(BindGenLike::from_isize(4), Some(BindGenLike::GHI));
+    assert_eq!(BindGenLike::from_u32(2), Some(BindGenLike::DEF));
+    assert_eq!(BindGenLike::from_u32(8), None);
+
+    let abc = BindGenLike::ABC;
+    assert_eq!(abc.to_u32(), Some(1));
+}
+```