diff -r ecbd252fd3a7 -r af170d42b5b3 javaquery/demo-calculator/src/main/java/org/apidesign/bck2brwsr/demo/calc/staticcompilation/Calc.java
--- a/javaquery/demo-calculator/src/main/java/org/apidesign/bck2brwsr/demo/calc/staticcompilation/Calc.java	Fri Mar 22 17:03:32 2013 +0100
+++ b/javaquery/demo-calculator/src/main/java/org/apidesign/bck2brwsr/demo/calc/staticcompilation/Calc.java	Mon Mar 25 11:50:36 2013 +0100
@@ -17,9 +17,11 @@
  */
 package org.apidesign.bck2brwsr.demo.calc.staticcompilation;
 
+import java.util.List;
 import org.apidesign.bck2brwsr.htmlpage.api.ComputedProperty;
 import org.apidesign.bck2brwsr.htmlpage.api.On;
 import static org.apidesign.bck2brwsr.htmlpage.api.OnEvent.*;
+import org.apidesign.bck2brwsr.htmlpage.api.OnFunction;
 import org.apidesign.bck2brwsr.htmlpage.api.Page;
 import org.apidesign.bck2brwsr.htmlpage.api.Property;
 
@@ -38,7 +40,7 @@
 })
 public class Calc {
     static {
-        new Calculator().applyBindings();
+        new Calculator().applyBindings().setOperation("plus");
     }
     
     @On(event = CLICK, id="clear")
@@ -76,6 +78,16 @@
         c.setMemory(0);
     }
     
+    @OnFunction
+    static void recoverMemory(Calculator c, double data) {
+        c.setDisplay(data);
+    }
+
+    @OnFunction
+    static void removeMemory(Calculator c, double data) {
+        c.getHistory().remove(data);
+    }
+    
     private static double compute(String op, double memory, double display) {
         switch (op) {
             case "plus": return memory + display;
@@ -112,4 +124,9 @@
         }
         return "Attempt to compute " + memory + " " + operation + " " + display + " = " + compute(operation, memory, display);
     }
+    
+    @ComputedProperty
+    static boolean emptyHistory(List<?> history) {
+        return history.isEmpty();
+    }
 }