1 files changed, 19 insertions, 1 deletions
diff --git a/stdlib/source/lux/data/sum.lux b/stdlib/source/lux/data/sum.lux
index a40aa4619..6a048153c 100644
--- a/stdlib/source/lux/data/sum.lux
+++ b/stdlib/source/lux/data/sum.lux
@@ -2,7 +2,8 @@
   {#.doc "Functionality for working with variants (particularly 2-variants)."}
   [lux #*
    [abstract
-    [equivalence (#+ Equivalence)]]])
+    [equivalence (#+ Equivalence)]
+    [hash (#+ Hash)]]])
 
 (template [<name> <type> <right?>]
   [(def: #export (<name> value)
@@ -73,3 +74,20 @@
 
       _
       false)))
+
+(structure: #export (hash (^open "l@.") (^open "r@."))
+  (All [l r]
+    (-> (Hash l) (Hash r)
+        (Hash (| l r))))
+
+  (def: &equivalence (..equivalence l@= r@=))
+
+  (def: (hash value)
+    (case value
+      (#.Left value)
+      (l@hash value)
+      
+      (#.Right value)
+      (.nat ("lux i64 *"
+             (.int 2)
+             (.int (r@hash value)))))))