1 files changed, 81 insertions, 0 deletions
diff --git a/examples/derive_ref/flatten_hand_args.rs b/examples/derive_ref/flatten_hand_args.rs
new file mode 100644
index 0000000..c10e0b2
--- /dev/null
+++ b/examples/derive_ref/flatten_hand_args.rs
@@ -0,0 +1,81 @@
+use clap::error::Error;
+use clap::{Arg, ArgAction, ArgMatches, Args, Command, FromArgMatches, Parser};
+
+#[derive(Debug)]
+struct CliArgs {
+    foo: bool,
+    bar: bool,
+    quuz: Option<String>,
+}
+
+impl FromArgMatches for CliArgs {
+    fn from_arg_matches(matches: &ArgMatches) -> Result<Self, Error> {
+        let mut matches = matches.clone();
+        Self::from_arg_matches_mut(&mut matches)
+    }
+    fn from_arg_matches_mut(matches: &mut ArgMatches) -> Result<Self, Error> {
+        Ok(Self {
+            foo: matches.get_flag("foo"),
+            bar: matches.get_flag("bar"),
+            quuz: matches.remove_one::<String>("quuz"),
+        })
+    }
+    fn update_from_arg_matches(&mut self, matches: &ArgMatches) -> Result<(), Error> {
+        let mut matches = matches.clone();
+        self.update_from_arg_matches_mut(&mut matches)
+    }
+    fn update_from_arg_matches_mut(&mut self, matches: &mut ArgMatches) -> Result<(), Error> {
+        self.foo |= matches.get_flag("foo");
+        self.bar |= matches.get_flag("bar");
+        if let Some(quuz) = matches.remove_one::<String>("quuz") {
+            self.quuz = Some(quuz);
+        }
+        Ok(())
+    }
+}
+
+impl Args for CliArgs {
+    fn augment_args(cmd: Command<'_>) -> Command<'_> {
+        cmd.arg(
+            Arg::new("foo")
+                .short('f')
+                .long("foo")
+                .action(ArgAction::SetTrue),
+        )
+        .arg(
+            Arg::new("bar")
+                .short('b')
+                .long("bar")
+                .action(ArgAction::SetTrue),
+        )
+        .arg(Arg::new("quuz").short('q').long("quuz").takes_value(true))
+    }
+    fn augment_args_for_update(cmd: Command<'_>) -> Command<'_> {
+        cmd.arg(
+            Arg::new("foo")
+                .short('f')
+                .long("foo")
+                .action(ArgAction::SetTrue),
+        )
+        .arg(
+            Arg::new("bar")
+                .short('b')
+                .long("bar")
+                .action(ArgAction::SetTrue),
+        )
+        .arg(Arg::new("quuz").short('q').long("quuz").takes_value(true))
+    }
+}
+
+#[derive(Parser, Debug)]
+struct Cli {
+    #[clap(short, long, action)]
+    top_level: bool,
+    #[clap(flatten)]
+    more_args: CliArgs,
+}
+
+fn main() {
+    let args = Cli::parse();
+    println!("{:#?}", args);
+}