--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/doc-src/TutorialI/Trie/document/Option2.tex Wed Apr 19 12:59:38 2000 +0200
@@ -0,0 +1,4 @@
+\begin{isabelle}%
+\isanewline
+\isacommand{datatype}~'a~option~=~None~|~Some~'a\isanewline
+\end{isabelle}%