diff -r eacce1cd716a -r 05fc32a23b8b doc-src/TutorialI/Misc/document/Tree.tex
--- a/doc-src/TutorialI/Misc/document/Tree.tex	Tue Aug 16 13:42:21 2005 +0200
+++ b/doc-src/TutorialI/Misc/document/Tree.tex	Tue Aug 16 13:42:23 2005 +0200
@@ -1,39 +1,81 @@
 %
 \begin{isabellebody}%
 \def\isabellecontext{Tree}%
-\isamarkupfalse%
+%
+\isadelimtheory
+%
+\endisadelimtheory
+%
+\isatagtheory
+%
+\endisatagtheory
+{\isafoldtheory}%
+%
+\isadelimtheory
+%
+\endisadelimtheory
+\isamarkuptrue%
 %
 \begin{isamarkuptext}%
 \noindent
 Define the datatype of \rmindex{binary trees}:%
 \end{isamarkuptext}%
-\isamarkuptrue%
-\isacommand{datatype}\ {\isacharprime}a\ tree\ {\isacharequal}\ Tip\ {\isacharbar}\ Node\ {\isachardoublequote}{\isacharprime}a\ tree{\isachardoublequote}\ {\isacharprime}a\ {\isachardoublequote}{\isacharprime}a\ tree{\isachardoublequote}\isamarkupfalse%
 \isamarkupfalse%
-\isamarkupfalse%
+\isacommand{datatype}\ {\isacharprime}a\ tree\ {\isacharequal}\ Tip\ {\isacharbar}\ Node\ {\isachardoublequote}{\isacharprime}a\ tree{\isachardoublequote}\ {\isacharprime}a\ {\isachardoublequote}{\isacharprime}a\ tree{\isachardoublequote}\isamarkuptrue%
 %
 \begin{isamarkuptext}%
 \noindent
 Define a function \isa{mirror} that mirrors a binary tree
 by swapping subtrees recursively. Prove%
 \end{isamarkuptext}%
+\isamarkupfalse%
+\isacommand{lemma}\ mirror{\isacharunderscore}mirror{\isacharcolon}\ {\isachardoublequote}mirror{\isacharparenleft}mirror\ t{\isacharparenright}\ {\isacharequal}\ t{\isachardoublequote}%
+\isadelimproof
+%
+\endisadelimproof
+%
+\isatagproof
+%
+\endisatagproof
+{\isafoldproof}%
+%
+\isadelimproof
+%
+\endisadelimproof
 \isamarkuptrue%
-\isacommand{lemma}\ mirror{\isacharunderscore}mirror{\isacharcolon}\ {\isachardoublequote}mirror{\isacharparenleft}mirror\ t{\isacharparenright}\ {\isacharequal}\ t{\isachardoublequote}\isamarkupfalse%
-\isamarkupfalse%
-\isamarkupfalse%
-\isamarkupfalse%
-\isamarkupfalse%
 %
 \begin{isamarkuptext}%
 \noindent
 Define a function \isa{flatten} that flattens a tree into a list
 by traversing it in infix order. Prove%
 \end{isamarkuptext}%
-\isamarkuptrue%
-\isacommand{lemma}\ {\isachardoublequote}flatten{\isacharparenleft}mirror\ t{\isacharparenright}\ {\isacharequal}\ rev{\isacharparenleft}flatten\ t{\isacharparenright}{\isachardoublequote}\isamarkupfalse%
 \isamarkupfalse%
-\isamarkupfalse%
-\isamarkupfalse%
+\isacommand{lemma}\ {\isachardoublequote}flatten{\isacharparenleft}mirror\ t{\isacharparenright}\ {\isacharequal}\ rev{\isacharparenleft}flatten\ t{\isacharparenright}{\isachardoublequote}%
+\isadelimproof
+%
+\endisadelimproof
+%
+\isatagproof
+%
+\endisatagproof
+{\isafoldproof}%
+%
+\isadelimproof
+%
+\endisadelimproof
+%
+\isadelimtheory
+%
+\endisadelimtheory
+%
+\isatagtheory
+%
+\endisatagtheory
+{\isafoldtheory}%
+%
+\isadelimtheory
+%
+\endisadelimtheory
 \end{isabellebody}%
 %%% Local Variables:
 %%% mode: latex