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diff --git a/lib/syntax_tools/examples/demo.erl b/lib/syntax_tools/examples/demo.erl
new file mode 100644
index 0000000000..53ba1372fd
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+++ b/lib/syntax_tools/examples/demo.erl
@@ -0,0 +1,80 @@
+%%
+%% Demo file for the Syntax Tools package.
+%%
+%% The program is self-instructing. Compile `demo' from the shell and
+%% execute `demo:run()'.
+
+-module(demo).
+
+-export([run/0, run_1/0, run_2/0, run_3/0, run_4/0, 
+	 view/1, view/2, view/3]).
+
+small_file() -> "test.erl".
+
+medium_file() -> "test_comprehensions.erl".
+
+big_file() -> "erl_comment_scan.erl".
+
+run() ->
+    make:all([load]),
+    io:fwrite("\n\n** Enter `demo:run_1()' to parse and pretty-print\n"
+	      "the file \"~s\" with the default field width.\n\n",
+	      [small_file()]),
+    ok.
+
+run_1() ->
+    view(small_file()),
+    io:fwrite("\n\n\n** Enter `demo:run_2()' to parse and pretty-print\n"
+	      "the file \"~s\" with a small field width.\n\n",
+	      [small_file()]),
+    ok.
+
+run_2() ->
+    view(small_file(), 15),
+    io:fwrite("\n\n\n** Enter `demo:run_3()' to parse and pretty-print\n"
+	      "the file \"~s\" with field width 35\n\n",
+	      [medium_file()]),
+    ok.
+
+run_3() ->
+   view(medium_file(), 35),
+    io:fwrite("\n\n\n** Enter `demo:run_4()' to parse and pretty-print\n"
+	      "the file \"~s\" with field width 55 and ribbon width 40.\n\n",
+	      [big_file()]),
+    ok.
+
+run_4() ->
+    view(big_file(), 55, 40),
+    io:fwrite("\n\n\n** Done! Now you can play around with the function\n"
+	      "`demo:view(FileName, PaperWidth, RibbonWidth)' on any\n"
+	      "Erlang source files you have around you.\n"
+	      "(Include the \".erl\" suffix in the file name.\n"
+	      "RibbonWidth and PaperWidth are optional.)\n\n"),
+    ok.
+
+view(Name) ->
+    SyntaxTree = read(Name),
+    print(SyntaxTree).
+
+view(Name, Paper) ->
+    SyntaxTree = read(Name),
+    print(SyntaxTree, Paper).
+
+view(Name, Paper, Ribbon) ->
+    SyntaxTree = read(Name),
+    print(SyntaxTree, Paper, Ribbon).
+
+print(SyntaxTree) ->
+    io:put_chars(erl_prettypr:format(SyntaxTree)).
+
+print(SyntaxTree, Paper) ->
+    io:put_chars(erl_prettypr:format(SyntaxTree, [{paper, Paper}])).
+
+print(SyntaxTree, Paper, Ribbon) ->
+    io:put_chars(erl_prettypr:format(SyntaxTree, [{paper, Paper},
+						  {ribbon, Ribbon}])).
+
+read(Name) ->
+    {ok, Forms} = epp:parse_file(Name, [], []),
+    Comments = erl_comment_scan:file(Name),
+    erl_recomment:recomment_forms(Forms, Comments).