no first load of config?

src/conf/mode.rs

@@ -1,5 +1,94 @@
 use crate::*;
 
+/// Has a stack of currently active interaction modes.
+pub trait HasModeStack {
+    /// Stack of active modes.
+    fn mode_stack (&self) -> &RwLock<Vec<Arc<str>>>;
+
+    fn mode_stack_push (&self, mode: impl AsRef<str>) {
+        self.mode_stack().write().push(mode.as_ref().into())
+    }
+}
+impl HasModeStack for App {
+    fn mode_stack (&self) -> &RwLock<Vec<Arc<str>>> {
+        &self.stack
+    }
+}
+
+/// Collection of UI modes.
+///
+/// ```
+/// # use tek::*;
+///
+/// // Empty mode registry:
+/// let state: Config = Default::default();
+/// assert_eq!(state.modes_count(), 0);
+/// assert!(state.modes_get("Foo").is_none());
+///
+/// // Add a mode:
+/// let _ = state.modes_add(&"Foo (name Foo) (info Bar)").unwrap();
+/// assert_eq!(state.modes_count(), 1);
+/// assert!(state.modes_get("Foo").is_some());
+/// ```
+pub trait HasModes {
+    fn modes (&self) -> &RwLock<BTreeMap<Arc<str>, Arc<Mode>>>;
+
+    /// Register a mode.
+    ///
+    /// ```
+    /// # use ::{std::sync::Arc, tek::*};
+    /// let config: Config = Default::default();
+    ///
+    /// config.modes_add(stringify!(Menu
+    ///   (name Menu) (info Mode selector.) (axis Y Index) (bind Confirm)
+    ///   (view (bg (g 30) (bar/s 7 Logo (full/xy Dialog))))
+    /// )).unwrap();
+    ///
+    /// let _: Arc<Mode> = config.modes_get("Menu").unwrap();
+    /// ```
+    fn modes_add <'a> (&self, expr: impl Language) -> UsuallyRef<'a, ()> {
+        let name = expr.head()?.ok_or("mode: missing name")?;
+        let body = expr.tail()?.ok_or("mode: missing body")?;
+        let mut mode = Mode::default();
+        body.each(&mut mode, |c, s|c.add(s))?;
+        self.modes().write().insert(name.into(), Arc::new(mode));
+        Ok(())
+    }
+    /// Get a mode by name.
+    fn modes_get (&self, name: impl AsRef<str>) -> Option<Arc<Mode>> {
+        self.modes().read().get(name.as_ref()).cloned()
+    }
+    /// Run something for each mode.
+    fn modes_for_each <T> (&self, mut ator: impl FnMut(&str, &Mode)->T) {
+        for (k, v) in self.modes().read().iter() {
+            let _ = ator(k.as_ref(), v.as_ref());
+        }
+    }
+    /// Count modes.
+    fn modes_count (&self) -> usize {
+        self.modes().read().len()
+    }
+    /// Clear modes.
+    fn modes_clear (&self) {
+        *self.modes().write() = Default::default();
+    }
+}
+impl HasModes for App {
+    fn modes (&self) -> &RwLock<BTreeMap<Arc<str>, Arc<Mode>>> {
+        &self.watch.config.modes
+    }
+}
+impl HasModes for Config {
+    fn modes (&self) -> &RwLock<BTreeMap<Arc<str>, Arc<Mode>>> {
+        &self.modes
+    }
+}
+impl HasModes for Mode {
+    fn modes (&self) -> &RwLock<BTreeMap<Arc<str>, Arc<Mode>>> {
+        &self.modes
+    }
+}
+
 impl_as_mut!(Mode: |self: Mode| self);
 
 /// Group of view and keys definitions.