feat: require renderers to return RenderResult instead of mutating one

BREAKING CHANGE: The `render` method on `Renderer`, `HelpRequest`, and
`ProgramCollect` now returns `RenderResult` instead of taking
`&mut RenderResult`. The `r_print!` and `r_println!` macros have been
removed in favor of using `std::io::Write` directly on `RenderResult`.

1 files changed, 1 insertions, 1 deletions

diff --git a/mingling_core/src/asset/renderer.rs b/mingling_core/src/asset/renderer.rs
index 1d5a2c1..732f9b7 100644
--- a/mingling_core/src/asset/renderer.rs
+++ b/mingling_core/src/asset/renderer.rs
@@ -6,5 +6,5 @@ pub trait Renderer {
     type Previous;
 
     /// Process the previous value and write the result into the provided [`RenderResult`](./struct.RenderResult.html)
-    fn render(p: Self::Previous, r: &mut RenderResult);
+    fn render(p: Self::Previous) -> RenderResult;
 }