Division and fixed pred

lib/base.tri

@@ -178,18 +178,15 @@ andLazy? = (a bK :
 
 pred = y (self : triage
   0
-  (_ : 0)
+  0
   (bit rest :
-    matchBool
-      (matchBool
+    ifLazy
+      bit
+      (_ : matchBool
+        (t t rest)
         0
-        (pair 0 rest)
-        (equal? rest 0))
-      (matchBool
-        0
-        (pair 1 (self rest))
-        (equal? rest 0))
-      bit))
+        rest)
+      (_ : t (t t) (self rest))))
 
 isZero? = triage true (_ : false) (_ _ : false)
 
@@ -231,6 +228,24 @@ mul = y (self a b :
     (_ : 0)
     (_ : add a (self a (pred b))))
 
+div = y (self a b :
+  ifLazy
+    (isZero? b)
+    (_ : 0)
+    (_ : ifLazy
+      (lt? a b)
+      (_ : 0)
+      (_ : succ (self (sub a b) b))))
+
+mod = y (self a b :
+  ifLazy
+    (isZero? b)
+    (_ : 0)
+    (_ : ifLazy
+      (lt? a b)
+      (_ : a)
+      (_ : self (sub a b) b)))
+
 -- ---------------------------------------------------------------------------
 -- Result combinators
 -- ---------------------------------------------------------------------------