From 06aa076c06bd1aca099ffd37de0feb8fa8166f3b Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Fri, 15 Apr 2022 18:18:34 +0100
Subject: [PATCH] Combine impls into impl_PieceSpec_for_SimplePieceSpec

We want to add load_inert to this.  It's getting too repetitive.

We can't use generic impl on <P: SimplePieceSpec> because we need to
specxify the serde typetag.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---
 src/pieces.rs | 28 ++++++++++++----------------
 1 file changed, 12 insertions(+), 16 deletions(-)

diff --git a/src/pieces.rs b/src/pieces.rs
index f6e5f867..9d9d7b78 100644
--- a/src/pieces.rs
+++ b/src/pieces.rs
@@ -332,15 +332,6 @@ impl SimplePieceSpec for piece_specs::Disc {
   }
 }
 
-#[typetag::serde]
-impl PieceSpec for piece_specs::Disc {
-  #[throws(SpecError)]
-  fn load(&self, _: usize, _: &mut GPiece, _ig: &Instance, _:SpecDepth)
-          -> PieceSpecLoaded {
-    SimplePieceSpec::load(self)?
-  }
-}
-
 impl piece_specs::Rect {
   #[throws(SpecError)]
   fn xy(&self) -> Pos {
@@ -370,11 +361,16 @@ impl SimplePieceSpec for piece_specs::Rect {
   }
 }
 
-#[typetag::serde]
-impl PieceSpec for piece_specs::Rect {
-  #[throws(SpecError)]
-  fn load(&self, _: usize, _: &mut GPiece, _ig: &Instance, _:SpecDepth)
-          -> PieceSpecLoaded {
-    SimplePieceSpec::load(self)?
+macro_rules! impl_PieceSpec_for_SimplePieceSpec { { $ty:ty } => {
+  #[typetag::serde]
+  impl PieceSpec for $ty {
+    #[throws(SpecError)]
+    fn load(&self, _: usize, _: &mut GPiece, _ig: &Instance, _:SpecDepth)
+            -> PieceSpecLoaded {
+      SimplePieceSpec::load(self)?
+    }
   }
-}
+} }
+
+impl_PieceSpec_for_SimplePieceSpec!{piece_specs::Disc}
+impl_PieceSpec_for_SimplePieceSpec!{piece_specs::Rect}
-- 
2.30.2