#clap [[®Doc comments]]で書く。 ```rust #[derive(Clap, Debug)] #[clap(version = "0.1", author = "tadashi-aikawa")] struct Opts { /// The path of the config file to load #[clap(short, long, default_value = ".tatsuwo.yaml")] config: String, } ``` `config`パラメータの説明に`The path of the config file to load`が表示される。サブコマンドの説明も同様。 ```rust #[derive(Clap, Debug)] enum SubCommand { /// タツヲが吠える Uho(UhoOpts), } ```