--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doc-src/Tutorial/Datatype/abdata	Thu Nov 12 16:45:40 1998 +0100
@@ -0,0 +1,9 @@
+datatype
+    'a aexp = IF ('a bexp) ('a aexp) ('a aexp)
+            | Sum ('a aexp) ('a aexp)
+            | Diff ('a aexp) ('a aexp)
+            | Var 'a
+            | Num nat
+and 'a bexp = Less ('a aexp) ('a aexp)
+            | And ('a bexp) ('a bexp)
+            | Neg ('a bexp)