From 2b5d493391d9435b7ce4922e300d79c908d865bf Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Thu, 12 May 2022 00:05:04 +0100
Subject: [PATCH] ambassador: impl_via_ambassador: Make it handle multiple

The result is quite nice.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---
 src/fastsplit.rs | 13 +++++--------
 src/utils.rs     | 12 +++++++-----
 2 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/src/fastsplit.rs b/src/fastsplit.rs
index 23622621..cfe90c00 100644
--- a/src/fastsplit.rs
+++ b/src/fastsplit.rs
@@ -59,15 +59,12 @@ impl Piece {
 impl_via_ambassador!{
   #[dyn_upcast]
   impl OutlineTrait for Piece { inner() } 
-}
 
-#[dyn_upcast]
-impl PieceBaseTrait for Piece {
-  ambassador_impl_PieceBaseTrait! {body_struct(<>, _, (), (inner()), ())}
-}
-#[typetag::serde(name="FastSplit")]
-impl PieceTrait for Piece {
-  ambassador_impl_PieceTrait! {body_struct(<>, _, (), (inner()), ())}
+  #[dyn_upcast]
+  impl PieceBaseTrait for Piece { inner() }
+
+  #[typetag::serde(name="FastSplit")]
+  impl PieceTrait for Piece { inner() }
 }
 
 impl Record {
diff --git a/src/utils.rs b/src/utils.rs
index f9b969c7..33da9663 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -776,10 +776,12 @@ paste!{
 #[macro_export]
 macro_rules! impl_via_ambassador{
   { 
-    $( #[ $attr:meta ] )*
-    impl $Trait:ident for $Type:ty
-    { $($how_immut:tt)* }
-  } => { paste!{
+    $(
+      $( #[ $attr:meta ] )*
+      impl $Trait:ident for $Type:ty
+      { $($how_immut:tt)* }
+    )*
+  } => { $( paste!{
     $( #[ $attr ] )*
     impl $Trait for $Type {
       [< ambassador_impl_ $Trait >]!{ body_struct( <>, dyn $Trait,
@@ -788,7 +790,7 @@ macro_rules! impl_via_ambassador{
           ()
       ) }
     }
-  } }
+  } )* }
 }
 
 #[macro_export]
-- 
2.30.2