# Procedural macro derive that mimics `arg_enum!` from [clap](https://clap.rs)


[](https://deps.rs/repo/github/lu-zero/arg_enum_proc_macro)
## Usage
In `Cargo.toml`:
``` toml
[dependencies]
arg_enum_proc_macro = "0.3"
```
In the rust code:
``` rust
use arg_enum_proc_macro::ArgEnum;
/// All the possible states of Foo
#[derive(ArgEnum)]
pub enum Foo {
/// Initial state
Unk,
/// Foo is on
On,
/// Foo is off
Off,
}
```
### Aliases
It is possible to express an alias using the attribute `arg_enum(alias = "AliasVariant")`.
The `FromStr` will map the "AliasVariant" string to the decorated enum variant:
``` rust
/// All the possible states of Foo
#[derive(ArgEnum)]
pub enum Foo {
/// Initial state
Unk,
/// Foo is on
#[arg_enum(alias = "Up")]
On,
/// Foo is off
#[arg_enum(alias = "Down")]
Off,
}
```