diff -r 000000000000 -r bc8c9a11cbfc test/idb/arithmetic.xml
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/idb/arithmetic.xml	Wed Oct 10 22:58:21 2012 +0100
@@ -0,0 +1,15 @@
+<expr>
+  <define name="x"><multiply>2 3</multiply></define>
+  <add><x/>3</add>
+  <print><x/></print>
+  <println/>
+
+  <define name="x"><multiply>2 3</multiply></define>
+  <add><x unused=""/>3</add>
+  <print><x/></print>
+  <println/>
+
+  <set name="x">5</set>
+  <add><x/><x/><x/></add>
+  <print newline="true"><x/></print>
+</expr>