Example of org-mode/tangle

gistfile1.txt

#+TITLE:     Example of using org/babel to do litterate programming
#+AUTHOR:    Ronan BARZIC
#+EMAIL:     ronan.barzic@onio.com

To "tangle" it : C-c C-v t

#+BEGIN_SRC python :noweb yes :tangle HelloWorld.py :exports none
"""This is a hello world example document"""

# imports
import sys
<<helloworld-main-imports>>

# constants

# exception classes

# interface functions

# classes
<<HelloWorld-defn>>

# internal functions & classes

<<helloworld-main>>

if __name__ == '__main__':
    status = main()
    sys.exit(status)
#+END_SRC


#+NAME: HelloWorld-defn
#+BEGIN_SRC python
  class HelloWorld(object):
      def __init__(self, who):
          self.who = who
  
      def say_hello(self):
          print "Hello %s" % self.who
#+END_SRC


#+NAME: helloworld-main-imports
#+BEGIN_SRC python
from argparse import ArgumentParser
#+END_SRC

#+NAME: helloworld-main
#+BEGIN_SRC python
  def main():
      parser = ArgumentParser(description="Say hi")
      parser.add_argument("-w", "--who", 
                          type=str,
                          default="world",
                          help="Who to say hello to")
      args = parser.parse_args()
  
      who = args.who
  
      greeter = HelloWorld(who)
      greeter.say_hello()
  
      return 0
#+END_SRC

This is another working example I use for scan pins. All inputs driven to '0 and all outputs open.
.(.scan.) (@"(if (equal vl-dir \"input\") \"'0\" \"\")"),

Here are some examples of using vl-dir. Based on dir the prefix name changes.
.(a.*) (@"(if (equal vl-dir \"input\") \"snoc_ddr_ss_ctgt_\1\" \"ddr_snoc_ss_ctgt_\1\")"),