Issue #10199: Fixing r86095 - svn did not like combining rename and change of directory.
diff --git a/Lib/turtledemo/lindenmayer.py b/Lib/turtledemo/lindenmayer.py
new file mode 100644
index 0000000..3925f25
--- /dev/null
+++ b/Lib/turtledemo/lindenmayer.py
@@ -0,0 +1,119 @@
+#!/usr/bin/env python3
+""" turtle-example-suite:
+
+ xtx_lindenmayer_indian.py
+
+Each morning women in Tamil Nadu, in southern
+India, place designs, created by using rice
+flour and known as kolam on the thresholds of
+their homes.
+
+These can be described by Lindenmayer systems,
+which can easily be implemented with turtle
+graphics and Python.
+
+Two examples are shown here:
+(1) the snake kolam
+(2) anklets of Krishna
+
+Taken from Marcia Ascher: Mathematics
+Elsewhere, An Exploration of Ideas Across
+Cultures
+
+"""
+################################
+# Mini Lindenmayer tool
+###############################
+
+from turtle import *
+
+def replace( seq, replacementRules, n ):
+ for i in range(n):
+ newseq = ""
+ for element in seq:
+ newseq = newseq + replacementRules.get(element,element)
+ seq = newseq
+ return seq
+
+def draw( commands, rules ):
+ for b in commands:
+ try:
+ rules[b]()
+ except TypeError:
+ try:
+ draw(rules[b], rules)
+ except:
+ pass
+
+
+def main():
+ ################################
+ # Example 1: Snake kolam
+ ################################
+
+
+ def r():
+ right(45)
+
+ def l():
+ left(45)
+
+ def f():
+ forward(7.5)
+
+ snake_rules = {"-":r, "+":l, "f":f, "b":"f+f+f--f--f+f+f"}
+ snake_replacementRules = {"b": "b+f+b--f--b+f+b"}
+ snake_start = "b--f--b--f"
+
+ drawing = replace(snake_start, snake_replacementRules, 3)
+
+ reset()
+ speed(3)
+ tracer(1,0)
+ ht()
+ up()
+ backward(195)
+ down()
+ draw(drawing, snake_rules)
+
+ from time import sleep
+ sleep(3)
+
+ ################################
+ # Example 2: Anklets of Krishna
+ ################################
+
+ def A():
+ color("red")
+ circle(10,90)
+
+ def B():
+ from math import sqrt
+ color("black")
+ l = 5/sqrt(2)
+ forward(l)
+ circle(l, 270)
+ forward(l)
+
+ def F():
+ color("green")
+ forward(10)
+
+ krishna_rules = {"a":A, "b":B, "f":F}
+ krishna_replacementRules = {"a" : "afbfa", "b" : "afbfbfbfa" }
+ krishna_start = "fbfbfbfb"
+
+ reset()
+ speed(0)
+ tracer(3,0)
+ ht()
+ left(45)
+ drawing = replace(krishna_start, krishna_replacementRules, 3)
+ draw(drawing, krishna_rules)
+ tracer(1)
+ return "Done!"
+
+if __name__=='__main__':
+ msg = main()
+ print(msg)
+ mainloop()