feat: add __args

__args/argh-test/src/main.rs

@@ -0,0 +1,22 @@
+use argh::FromArgs;
+
+#[derive(Debug, FromArgs)]
+/// Reach new heights.
+struct GoUp {
+    /// whether or not to jump
+    #[argh(switch, short = 'j')]
+    jump: bool,
+
+    /// how high to go
+    #[argh(option)]
+    height: usize,
+
+    /// an optional nickname for the pilot
+    #[argh(option)]
+    pilot_nickname: Option<String>,
+}
+
+fn main() {
+    let up: GoUp = argh::from_env();
+    println!("{:#?}", up);
+}