1 files changed, 16 insertions, 13 deletions
diff --git a/stdlib/source/lux/abstract/interval.lux b/stdlib/source/lux/abstract/interval.lux
index fbe3a4c8a..e43529890 100644
--- a/stdlib/source/lux/abstract/interval.lux
+++ b/stdlib/source/lux/abstract/interval.lux
@@ -6,7 +6,7 @@
    ["." order]
    [enum (#+ Enum)]])
 
-(signature: #export (Interval a)
+(interface: #export (Interval a)
   {#.doc "A representation of top and bottom boundaries for an ordered type."}
   (: (Enum a)
      &enum)
@@ -19,14 +19,14 @@
 
 (def: #export (between enum bottom top)
   (All [a] (-> (Enum a) a a (Interval a)))
-  (structure
+  (implementation
    (def: &enum enum)
    (def: bottom bottom)
    (def: top top)))
 
 (def: #export (singleton enum elem)
   (All [a] (-> (Enum a) a (Interval a)))
-  (structure
+  (implementation
    (def: &enum enum)
    (def: bottom elem)
    (def: top elem)))
@@ -74,22 +74,25 @@
 
 (def: #export (union left right)
   (All [a] (-> (Interval a) (Interval a) (Interval a)))
-  (structure (def: &enum (get@ #&enum right))
-             (def: bottom (order.min (\ right &order) (\ left bottom) (\ right bottom)))
-             (def: top (order.max (\ right &order) (\ left top) (\ right top)))))
+  (implementation
+   (def: &enum (get@ #&enum right))
+   (def: bottom (order.min (\ right &order) (\ left bottom) (\ right bottom)))
+   (def: top (order.max (\ right &order) (\ left top) (\ right top)))))
 
 (def: #export (intersection left right)
   (All [a] (-> (Interval a) (Interval a) (Interval a)))
-  (structure (def: &enum (get@ #&enum right))
-             (def: bottom (order.max (\ right &order) (\ left bottom) (\ right bottom)))
-             (def: top (order.min (\ right &order) (\ left top) (\ right top)))))
+  (implementation
+   (def: &enum (get@ #&enum right))
+   (def: bottom (order.max (\ right &order) (\ left bottom) (\ right bottom)))
+   (def: top (order.min (\ right &order) (\ left top) (\ right top)))))
 
 (def: #export (complement interval)
   (All [a] (-> (Interval a) (Interval a)))
   (let [(^open ".") interval]
-    (structure (def: &enum (get@ #&enum interval))
-               (def: bottom (succ top))
-               (def: top (pred bottom)))))
+    (implementation
+     (def: &enum (get@ #&enum interval))
+     (def: bottom (succ top))
+     (def: top (pred bottom)))))
 
 (def: #export (precedes? reference sample)
   (All [a] (-> (Interval a) (Interval a) Bit))
@@ -139,7 +142,7 @@
   [finishes? ,\top    order.>= ,\bottom]
   )
 
-(structure: #export equivalence (All [a] (Equivalence (Interval a)))
+(implementation: #export equivalence (All [a] (Equivalence (Interval a)))
   (def: (= reference sample)
     (let [(^open ",\.") reference]
       (and (,\= ,\bottom (\ sample bottom))