doc-src/Codegen/Thy/examples/example.ML
changeset 30226 2f4684e2ea95
parent 29798 6df726203e39
child 33707 68841fb382e0
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doc-src/Codegen/Thy/examples/example.ML	Tue Mar 03 11:00:51 2009 +0100
@@ -0,0 +1,27 @@
+structure Example = 
+struct
+
+fun foldl f a [] = a
+  | foldl f a (x :: xs) = foldl f (f a x) xs;
+
+fun rev xs = foldl (fn xsa => fn x => x :: xsa) [] xs;
+
+fun list_case f1 f2 (a :: lista) = f2 a lista
+  | list_case f1 f2 [] = f1;
+
+datatype 'a queue = AQueue of 'a list * 'a list;
+
+val empty : 'a queue = AQueue ([], [])
+
+fun dequeue (AQueue ([], [])) = (NONE, AQueue ([], []))
+  | dequeue (AQueue (xs, y :: ys)) = (SOME y, AQueue (xs, ys))
+  | dequeue (AQueue (v :: va, [])) =
+    let
+      val y :: ys = rev (v :: va);
+    in
+      (SOME y, AQueue ([], ys))
+    end;
+
+fun enqueue x (AQueue (xs, ys)) = AQueue (x :: xs, ys);
+
+end; (*struct Example*)