From ed6683797f28366e8bbbc2846b3bb71df7127812 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Sat, 27 Jun 2020 13:51:24 +0100
Subject: [PATCH] impl slotmap::Key

---
 src/keydata.rs | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/keydata.rs b/src/keydata.rs
index 60e2e2a7..44b2ea51 100644
--- a/src/keydata.rs
+++ b/src/keydata.rs
@@ -37,7 +37,8 @@ pub fn slotkey_write(k : SKD, sep : char, f : &mut fmt::Formatter) {
 #[macro_export]
 macro_rules! visible_slotmap_key {
   ( $x:ident ) => {
-    #[derive(Copy,Clone,Serialize,Deserialize)]
+
+    #[derive(Copy,Clone,Eq,PartialEq,Ord,PartialOrd,Serialize,Deserialize)]
     #[serde(into="String")]
     #[serde(try_from="&str")]
     pub struct $x(pub slotmap::KeyData);
@@ -54,6 +55,16 @@ macro_rules! visible_slotmap_key {
         VisiblePieceId(slotkey_parse(s,'.')?)
       }
     }
+
+    impl slotmap::Key for $x { }
+    impl From<slotmap::KeyData> for $x {
+      fn from(d : slotmap::KeyData) -> Self { $x(d) }
+    }
+    impl From<$x> for slotmap::KeyData {
+      fn from(p : $x) -> Self {
+        p.0
+      }
+    }
   }
 }
 pub use crate::visible_slotmap_key; // this is madness!
-- 
2.30.2