Procedural macro derive that mimics arg_enum! from clap

Usage

In Cargo.toml: toml [dependencies] arg_enum_proc_macro = "0.1"

In the rust code: ``` rust use argenumproc_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 #[argenum(alias = "Up")] On, /// Foo is off #[argenum(alias = "Down")] Off, } ```