extract tui support code to tek_tui

engine/src/lib.rs

@@ -5,8 +5,6 @@ mod engine; pub use self::engine::*;
 mod input;  pub use self::input::*;
 mod output; pub use self::output::*;
 
-pub mod tui;
-
 pub use std::error::Error;
 
 /// Standard result type.
@@ -15,6 +13,16 @@ 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_dimensions () {
     assert_eq!(Area::center(&[10u16, 10, 20, 20]), [20, 20]);
 }