Box::deref makes the EDN rendering examples really work!

engine/src/output/render.rs

@@ -1,4 +1,5 @@
 use crate::*;
+use std::ops::Deref;
 
 /// Custom layout and rendering.
 pub trait Render<E: Engine>: Send + Sync {
@@ -8,11 +9,57 @@ pub trait Render<E: Engine>: Send + Sync {
         Box::new(self) as RenderBox<'a, E>
     }
 }
+
 pub type RenderDyn<'a, Engine> = dyn Render<Engine> + 'a;
 impl<'a, E: Engine> Content<E> for &RenderDyn<'a, E> where Self: Sized {
-    fn content (&self) -> impl Render<E> { self }
+    fn content (&self) -> impl Render<E> { *self }
+    fn layout (&self, area: E::Area) -> E::Area { Render::layout(self.deref(), area) }
+    fn render (&self, output: &mut E::Output) { Render::render(self.deref(), output) }
 }
+
 pub type RenderBox<'a, E: Engine> = Box<RenderDyn<'a, E>>;
 impl<'a, E: Engine> Content<E> for RenderBox<'a, E> {
-    fn content (&self) -> impl Render<E> { self }
+    fn content (&self) -> impl Render<E> { self.deref() }
+}
+
+impl<E: Engine, C: Content<E>> Render<E> for C {
+    fn layout (&self, area: E::Area) -> E::Area { Content::layout(self, area) }
+    fn render (&self, output: &mut E::Output) { Content::render(self, output) }
+}
+
+#[macro_export] macro_rules! render {
+    (($self:ident:$Struct:ty) => $content:expr) => {
+        impl <E: Engine> Content<E> for $Struct {
+            fn content (&$self) -> impl Render<E> { Some($content) }
+        }
+    };
+    (|$self:ident:$Struct:ident $(<
+        $($L:lifetime),* $($T:ident $(:$Trait:path)?),*
+    >)?, $to:ident | $render:expr) => {
+        impl <$($($L),*)? E: Engine, $($T$(:$Trait)?),*> Content<E>
+        for $Struct $(<$($L),* $($T),*>>)? {
+            fn render (&$self, $to: &mut E::Output) { $render }
+        }
+    };
+    ($Engine:ty:
+        ($self:ident:$Struct:ident $(<$(
+            $($L:lifetime)? $($T:ident)? $(:$Trait:path)?
+        ),+>)?) => $content:expr
+    ) => {
+        impl $(<$($($L)? $($T)? $(:$Trait)?),+>)? Content<$Engine>
+        for $Struct $(<$($($L)? $($T)?),+>)? {
+            fn content (&$self) -> impl Render<$Engine> { $content }
+        }
+    };
+
+    ($Engine:ty:
+        |$self:ident : $Struct:ident $(<$(
+            $($L:lifetime)? $($T:ident)? $(:$Trait:path)?
+        ),+>)?, $to:ident| $render:expr
+    ) => {
+        impl $(<$($($L)? $($T)? $(:$Trait)?),+>)? Content<$Engine>
+        for $Struct $(<$($($L)? $($T)?),+>)? {
+            fn render (&$self, $to: &mut <$Engine as Engine>::Output) { $render }
+        }
+    };
 }