refactor engine and layout into input and output

output/src/lib.rs

@@ -0,0 +1,82 @@
+#![feature(type_alias_impl_trait)]
+#![feature(impl_trait_in_assoc_type)]
+
+mod coordinate; pub use self::coordinate::*;
+mod size; pub use self::size::*;
+mod area; pub use self::area::*;
+
+mod output;  pub use self::output::*;
+mod content; pub use self::content::*;
+mod render;  pub use self::render::*;
+mod thunk;   pub use self::thunk::*;
+
+mod when;   pub use self::when::*;
+mod either; pub use self::either::*;
+mod map;    pub use self::map::*;
+mod reduce; pub use self::reduce::*;
+
+mod align;              pub use self::align::*;
+mod direction;          pub use self::direction::*;
+mod measure;            pub use self::measure::*;
+mod transform_xy;       pub use self::transform_xy::*;
+mod transform_xy_unit;  pub use self::transform_xy_unit::*;
+
+pub(crate) use std::marker::PhantomData;
+pub(crate) use std::error::Error;
+
+/// Standard result type.
+pub type Usually<T> = Result<T, Box<dyn Error>>;
+
+/// Standard optional result type.
+pub type Perhaps<T> = Result<Option<T>, Box<dyn Error>>;
+
+/// Prototypal case of implementor macro.
+/// Saves 4loc per data pats.
+#[macro_export] macro_rules! from {
+    ($(<$($lt:lifetime),+>)?|$state:ident:$Source:ty|$Target:ty=$cb:expr) => {
+        impl $(<$($lt),+>)? From<$Source> for $Target {
+            fn from ($state:$Source) -> Self { $cb }
+        }
+    };
+}
+
+#[cfg(test)] #[test] fn test_layout () -> Usually<()> {
+    use ::tek_tui::Tui;
+    let area: [u16;4] = [10, 10, 20, 20];
+
+    let unit = ();
+
+    assert_eq!(Content::<TuiOut>::layout(&unit, area), [20, 20, 0, 0]);
+
+    assert_eq!(Fill::<TuiOut>::x(unit).layout(area),  [10, 20, 20, 0]);
+    assert_eq!(Fill::<TuiOut>::y(unit).layout(area),  [20, 10, 0, 20]);
+    assert_eq!(Fill::<TuiOut>::xy(unit).layout(area), area);
+
+    assert_eq!(Fixed::<TuiOut, u16>::x(4, unit).layout(area),     [18, 20, 4, 0]);
+    assert_eq!(Fixed::<TuiOut, u16>::y(4, unit).layout(area),     [20, 18, 0, 4]);
+    assert_eq!(Fixed::<TuiOut, u16>::xy(4, 4, unit).layout(area), [18, 18, 4, 4]);
+
+    let four = ||Fixed::<TuiOut>::xy(4, 4, unit);
+
+    assert_eq!(Align::nw(four()).layout(area), [10, 10, 4, 4]);
+    assert_eq!(Align::n(four()).layout(area),  [18, 10, 4, 4]);
+    assert_eq!(Align::ne(four()).layout(area), [26, 10, 4, 4]);
+    assert_eq!(Align::e(four()).layout(area),  [26, 18, 4, 4]);
+    assert_eq!(Align::se(four()).layout(area), [26, 26, 4, 4]);
+    assert_eq!(Align::s(four()).layout(area),  [18, 26, 4, 4]);
+    assert_eq!(Align::sw(four()).layout(area), [10, 26, 4, 4]);
+    assert_eq!(Align::w(four()).layout(area),  [10, 18, 4, 4]);
+
+    let two_by_four = ||Fixed::<TuiOut>::xy(4, 2, unit);
+
+    assert_eq!(Align::nw(two_by_four()).layout(area), [10, 10, 4, 2]);
+    assert_eq!(Align::n(two_by_four()).layout(area),  [18, 10, 4, 2]);
+    assert_eq!(Align::ne(two_by_four()).layout(area), [26, 10, 4, 2]);
+    assert_eq!(Align::e(two_by_four()).layout(area),  [26, 19, 4, 2]);
+    assert_eq!(Align::se(two_by_four()).layout(area), [26, 28, 4, 2]);
+    assert_eq!(Align::s(two_by_four()).layout(area),  [18, 28, 4, 2]);
+    assert_eq!(Align::sw(two_by_four()).layout(area), [10, 28, 4, 2]);
+    assert_eq!(Align::w(two_by_four()).layout(area),  [10, 19, 4, 2]);
+
+    Ok(())
+}