1 files changed, 73 insertions, 7 deletions
diff --git a/Lib/turtledemo/__main__.py b/Lib/turtledemo/__main__.py
index a14684c..958c283 100755
--- a/Lib/turtledemo/__main__.py
+++ b/Lib/turtledemo/__main__.py
@@ -1,12 +1,81 @@
 #!/usr/bin/env python3
+
+"""
+  ----------------------------------------------
+
+      turtledemo - Help
+
+  ----------------------------------------------
+
+  This document has two sections:
+
+  (1) How to use the demo viewer
+  (2) How to add your own demos to the demo repository
+
+
+  (1) How to use the demo viewer.
+
+  Select a demoscript from the example menu.
+  The (syntax coloured) source code appears in the left
+  source code window. IT CANNOT BE EDITED, but ONLY VIEWED!
+
+  - Press START button to start the demo.
+  - Stop execution by pressing the STOP button.
+  - Clear screen by pressing the CLEAR button.
+  - Restart by pressing the START button again.
+
+  SPECIAL demos are those which run EVENTDRIVEN.
+  (For example clock.py - or oldTurtleDemo.py which
+  in the end expects a mouse click.):
+
+      Press START button to start the demo.
+
+      - Until the EVENTLOOP is entered everything works
+      as in an ordinary demo script.
+
+      - When the EVENTLOOP is entered, you control the
+      application by using the mouse and/or keys (or it's
+      controlled by some timer events)
+      To stop it you can and must press the STOP button.
+
+      While the EVENTLOOP is running, the examples menu is disabled.
+
+      - Only after having pressed the STOP button, you may
+      restart it or choose another example script.
+
+   * * * * * * * *
+   In some rare situations there may occur interferences/conflicts
+   between events concerning the demo script and those concerning the
+   demo-viewer. (They run in the same process.) Strange behaviour may be
+   the consequence and in the worst case you must close and restart the
+   viewer.
+   * * * * * * * *
+
+
+   (2) How to add your own demos to the demo repository
+
+   - place: same directory as turtledemo/__main__.py
+
+   - requirements on source code:
+       code must contain a main() function which will
+       be executed by the viewer (see provided example scripts)
+       main() may return a string which will be displayed
+       in the Label below the source code window (when execution
+       has finished.)
+
+       !! For programs, which are EVENT DRIVEN, main must return
+       !! the string "EVENTLOOP". This informs the viewer, that the
+       !! script is still running and must be stopped by the user!
+"""
 import sys
 import os
 
 from tkinter import *
 from idlelib.Percolator import Percolator
 from idlelib.ColorDelegator import ColorDelegator
-from idlelib.textView import view_file # TextViewer
+from idlelib.textView import view_text # TextViewer
 from importlib import reload
+from turtledemo import __doc__ as about_turtledemo
 
 import turtle
 import time
@@ -28,16 +97,13 @@ def getExampleEntries():
             entry.endswith(".py") and entry[0] != '_']
 
 def showDemoHelp():
-    view_file(demo.root, "Help on turtleDemo",
-              os.path.join(demo_dir, "demohelp.txt"))
+    view_text(demo.root, "Help on turtledemo", __doc__)
 
 def showAboutDemo():
-    view_file(demo.root, "About turtleDemo",
-              os.path.join(demo_dir, "about_turtledemo.txt"))
+    view_text(demo.root, "About turtledemo", about_turtledemo)
 
 def showAboutTurtle():
-    view_file(demo.root, "About the new turtle module.",
-              os.path.join(demo_dir, "about_turtle.txt"))
+    view_text(demo.root, "About the turtle module.", turtle.__doc__)
 
 class DemoWindow(object):