feat: add pick_or, pick_or_default, and pick_or_route shorthands

Remove the `Default` bound from `pick()` and `EntryPicker::pick()`,
allowing non-Default types to be used as arguments.

Add `IntoPicker::pick_or`, `pick_or_default`, and `pick_or_route`
convenience methods for common fallback patterns.

Fix token splitting in `arg!` macro to correctly handle angle brackets.

3 files changed, 86 insertions, 5 deletions

diff --git a/arg_picker/src/picker.rs b/arg_picker/src/picker.rs
index f31a5b6..f722fb5 100644
--- a/arg_picker/src/picker.rs
+++ b/arg_picker/src/picker.rs
@@ -369,11 +369,83 @@ pub trait IntoPicker<'a> {
     fn pick<N>(self, arg: impl Into<&'a PickerArg<'a, N>>) -> PickerPattern1<'a, N, ()>
     where
         Self: Sized,
-        N: Pickable<'a> + Default + Sized,
+        N: Pickable<'a> + Sized,
     {
         Picker::build_pattern1(self.to_picker().args, arg.into(), None::<()>)
     }
 
+    /// Starts building a picker pattern with the first argument, using a default value provider.
+    ///
+    /// This is a shorthand for calling `.pick(arg).or(func)`.
+    ///
+    /// # Type Parameters
+    ///
+    /// * `Next` — The nominal type of the first argument; must implement [`Pickable`].
+    ///
+    /// # Parameters
+    ///
+    /// * `arg` — The argument definition, typically obtained from [`crate::macros::arg`].
+    /// * `func` — A closure that provides a default value if the arg is not provided by the user.
+    fn pick_or<Next, F>(
+        self,
+        arg: impl Into<&'a PickerArg<'a, Next>>,
+        func: F,
+    ) -> PickerPattern1<'a, Next, ()>
+    where
+        Self: Sized,
+        Next: Pickable<'a> + Sized,
+        F: FnMut() -> Next + 'static,
+    {
+        self.pick(arg).or(func)
+    }
+
+    /// Starts building a picker pattern with the first argument, using a default value.
+    ///
+    /// This is a shorthand for calling `.pick(arg).or_default()`.
+    ///
+    /// # Type Parameters
+    ///
+    /// * `Next` — The nominal type of the first argument; must implement [`Pickable`] and [`Default`].
+    ///
+    /// # Parameters
+    ///
+    /// * `arg` — The argument definition, typically obtained from [`crate::macros::arg`].
+    fn pick_or_default<Next>(
+        self,
+        arg: impl Into<&'a PickerArg<'a, Next>>,
+    ) -> PickerPattern1<'a, Next, ()>
+    where
+        Self: Sized,
+        Next: Pickable<'a> + Default + Sized,
+    {
+        self.pick(arg).or_default()
+    }
+
+    /// Starts building a picker pattern with the first argument, using a route if the arg is not provided.
+    ///
+    /// This is a shorthand for calling `.pick(arg).or_route(func)`.
+    ///
+    /// # Type Parameters
+    ///
+    /// * `Next` — The nominal type of the first argument; must implement [`Pickable`].
+    ///
+    /// # Parameters
+    ///
+    /// * `arg` — The argument definition, typically obtained from [`crate::macros::arg`].
+    /// * `func` — A closure that produces a route value if the arg is not provided by the user.
+    fn pick_or_route<Next, F, Route>(
+        self,
+        arg: impl Into<&'a PickerArg<'a, Next>>,
+        func: F,
+    ) -> PickerPattern1<'a, Next, Route>
+    where
+        Self: Sized,
+        Next: Pickable<'a> + Sized,
+        F: FnMut() -> Route + 'static,
+    {
+        self.pick(arg).with_route::<Route>().or_route(func)
+    }
+
     /// Converts the value into a `Picker` with a specified route type.
     ///
     /// This method allows changing the route (phantom type parameter) of the picker.
diff --git a/arg_picker_macros/src/arg.rs b/arg_picker_macros/src/arg.rs
index 55860c4..20731b1 100644
--- a/arg_picker_macros/src/arg.rs
+++ b/arg_picker_macros/src/arg.rs
@@ -119,6 +119,7 @@ pub(crate) fn arg(input: TokenStream) -> TokenStream {
 fn split_at_commas(tokens: &[TokenTree]) -> Vec<Vec<TokenTree>> {
     let mut result = vec![Vec::new()];
     let mut depth = 0u32;
+    let mut angle_depth = 0u32;
     for t in tokens {
         match t {
             TokenTree::Group(_g) => {
@@ -126,7 +127,15 @@ fn split_at_commas(tokens: &[TokenTree]) -> Vec<Vec<TokenTree>> {
                 result.last_mut().unwrap().push(t.clone());
                 depth -= 1;
             }
-            TokenTree::Punct(p) if p.as_char() == ',' && depth == 0 => {
+            TokenTree::Punct(p) if p.as_char() == '<' => {
+                angle_depth += 1;
+                result.last_mut().unwrap().push(t.clone());
+            }
+            TokenTree::Punct(p) if p.as_char() == '>' && angle_depth > 0 => {
+                angle_depth -= 1;
+                result.last_mut().unwrap().push(t.clone());
+            }
+            TokenTree::Punct(p) if p.as_char() == ',' && depth == 0 && angle_depth == 0 => {
                 result.push(Vec::new());
             }
             _ => result.last_mut().unwrap().push(t.clone()),
diff --git a/mingling/src/picker/entry_picker.rs b/mingling/src/picker/entry_picker.rs
index 7364c50..d9fb37c 100644
--- a/mingling/src/picker/entry_picker.rs
+++ b/mingling/src/picker/entry_picker.rs
@@ -35,7 +35,7 @@ pub trait EntryPicker<'a, This> {
     ) -> PickerPattern1<'a, Next, ChainProcess<This>>
     where
         Self: Sized,
-        Next: Pickable<'a> + Default + Sized,
+        Next: Pickable<'a> + Sized,
     {
         let picker = Self::to_picker(self);
         Picker::build_pattern1(picker.into_args(), arg.into(), None)
@@ -60,7 +60,7 @@ pub trait EntryPicker<'a, This> {
     ) -> PickerPattern1<'a, Next, ChainProcess<This>>
     where
         Self: Sized,
-        Next: Pickable<'a> + Default + Sized,
+        Next: Pickable<'a> + Sized,
         F: FnMut() -> Next + 'static,
     {
         self.pick(arg).or(func)
@@ -107,7 +107,7 @@ pub trait EntryPicker<'a, This> {
     ) -> PickerPattern1<'a, Next, ChainProcess<This>>
     where
         Self: Sized,
-        Next: Pickable<'a> + Default + Sized,
+        Next: Pickable<'a> + Sized,
         F: FnMut() -> ChainProcess<This> + 'static,
     {
         self.pick(arg).or_route(func)