allow exiting via flag

examples/mode_02.rs

@@ -42,7 +42,9 @@ impl_keywords!(Tui, XYWH<u16>, State [
     kw_push,
     kw_tui_text,
     kw_tui_fg,
-    kw_tui_bg
+    kw_tui_bg,
+    kw_color_g,
+    kw_color_rgb,
 ]);
 
 impl Interpret<Tui, Option<XYWH<u16>>> for State {

src/layout/azimuth.rs

@@ -38,7 +38,6 @@ fn_kw_layout!(kw_align |state, output, expr| {
         draw(move|output: &mut O|{state.interpret(output, &expr.tail().head())}).align(
             eval_enum!("align", output, state,
                 expr.head().src()?.unwrap_or_default().split("/").skip(1).next(),
-                expr.tail().head(),
                 Azimuth {
                     "c" => C, "x" => X, "y" => Y,
                     "n" => N, "s" => S, "e" => E, "w" => W,
@@ -131,7 +130,7 @@ fn_kw_layout!(kw_split |state, output, expr| {
     let head = expr.head();
     let mut frags = head.src()?.unwrap_or_default().split("/");
     Ok(matches!(frags.next(), Some("bsp")).then(||{
-        eval_enum!("bsp", output, state, frags.next(), expr.tail().head()?, Split {
+        eval_enum!("bsp", output, state, frags.next(), Split {
             "n" => North,
             "s" => South,
             "e" => East,
@@ -140,10 +139,10 @@ fn_kw_layout!(kw_split |state, output, expr| {
             "b" => Below
         }).stack(
             draw(move|output: &mut O|{
-                state.interpret(output, &expr.tail().tail().head()?)
+                state.interpret(output, &expr.tail().head()?)
             }),
             draw(move|output: &mut O|{
-                state.interpret(output, &expr.tail().tail().tail().head()?)
+                state.interpret(output, &expr.tail().tail().head()?)
             }),
         ).draw(output)
     }).transpose()?.flatten())

src/layout/iter.rs

@@ -43,10 +43,23 @@ pub fn iter_east_fixed <'a, S: Screen, D: 'a, I: Iterator<Item = D>, U: Draw<S>>
     draw(move|_to: &mut S|{ todo!() })
 }
 
-pub fn iter_south <'a, S: Screen, D: 'a, I: Iterator<Item = D>, U: Draw<S>> (
-    _iter: impl Fn()->I, _draw: impl Fn(D, usize)->U,
+pub fn iter_south <'a, S: Screen, D: Draw<S>, I: Iterator<Item = D>> (
+    iter: impl Fn()->I
 ) -> impl Draw<S> {
-    draw(move|_to: &mut S|{ todo!() })
+    draw(move|to: &mut S|{
+        let XYWH(x, mut y, w, mut h) = to.area();
+        let h0 = h;
+        for item in iter() {
+            if let Some(used) = to.draw(Some(XYWH(x, y, w, h)), item)? {
+                y = y.add(used.y());
+                h = h.minus(used.y());
+                if h == S::Unit::zero() {
+                    break;
+                }
+            }
+        }
+        Ok(Some(XYWH(x, y, w, h)))
+    })
 }
 
 pub fn iter_south_fixed <'a, S: Screen, D: 'a, I: Iterator<Item = D>, U: Draw<S>> (

src/lib.rs

@@ -182,7 +182,7 @@ pub trait AsMutOpt<T> { fn as_mut_opt (&mut self) -> Option<&mut T>; }
 /// Some layout operations exist in multiple variants that take a single argument.
 /// Their handling in [eval_view] is uniform and goes like this:
 macro_rules! eval_enum ((
-    $name:literal, $output:ident, $state:ident, $value:expr, $arg0:expr, $Enum:ident {
+    $name:literal, $output:ident, $state:ident, $value:expr, $Enum:ident {
         $($v:literal => $V:ident),* $(,)?
     }
 ) => {{
@@ -252,10 +252,11 @@ macro_rules! eval_xy (
 #[cfg(feature = "exit")] pub use self::exit::*;
 #[cfg(feature = "exit")] mod exit {
     use crate::*;
-    use std::sync::{Arc, atomic::AtomicBool};
+    use std::sync::{Arc, atomic::{AtomicBool, Ordering::Relaxed}};
     use crossterm::event::*;
 
-    #[derive(Clone)] pub struct Exit(Arc<AtomicBool>);
+    #[derive(Clone, Default, Debug)]
+    pub struct Exit(Arc<AtomicBool>);
 
     impl Exit {
         pub fn run <T> (run: impl FnOnce(Self)->Usually<T>) -> Usually<T> {
@@ -269,6 +270,9 @@ macro_rules! eval_xy (
                 state:     KeyEventState::NONE
             }))
         }
+        pub fn exit (&self) {
+            self.0.store(true, Relaxed)
+        }
     }
 
     impl AsRef<Arc<AtomicBool>> for Exit {

src/term.rs

@@ -145,16 +145,14 @@ impl Tui {
             panic(info);
         }));
     }
-    pub fn run_main <T> (state: Arc<RwLock<T>>) -> Usually<()> where
+    pub fn run_main <T> (exit: Exit, state: Arc<RwLock<T>>) -> Usually<()> where
         T: View<Tui> + Apply<TuiEvent, Usually<()>> + Send + Sync + 'static
     {
-        Exit::run(|exit|{
-            let scan  = Duration::from_millis(100);
-            let frame = Duration::from_millis(10);
-            let (_input, output) = Tui::io(exit.as_ref(), &state, scan, frame, std::io::stdout())?;
-            let _ = output.join();
-            Tui::teardown(&mut stdout())
-        })
+        let scan  = Duration::from_millis(100);
+        let frame = Duration::from_millis(10);
+        let (_input, output) = Tui::io(exit.as_ref(), &state, scan, frame, std::io::stdout())?;
+        let _ = output.join();
+        Tui::teardown(&mut stdout())
     }
     /// Spawn the TUI input and output threadsl.
     pub fn io <
@@ -500,7 +498,7 @@ impl<T: Draw<Tui>> Draw<Tui> for ShowSizeOf<T> {
     }
 }
 
-#[cfg(feature = "eval")] fn_kw_layout_tui!(kw_tui_text |state, output, expr| {
+#[cfg(feature = "eval")] fn_kw_layout_tui!(kw_tui_text |_state, output, expr| {
     Ok(matches!(expr.head()?, Some("text")).then(||{
         if let Some(src) = expr.tail().src()? {
             src.draw(output)

src/term/modify.rs

@@ -36,7 +36,8 @@ impl Tui {
         if let Some(expr) = src.expr()? {
             match (expr.head()?, expr.tail()?) {
                 (Some("g"), Some(tail)) => {
-                    let n: u8 = state.namespace(tail.head().map_err(Into::into))?.ok_or(LanguageError::Domain("not gray"))?;
+                    let n: u8 = state.namespace(tail.head().map_err(Into::into))?
+                        .ok_or(LanguageError::Domain("not gray"))?;
                     Ok(Some(Color::Rgb(n, n, n)))
                 },
                 (Some("rgb"), Some(tail)) => {