#!/usr/bin/env python
""" Change all files in this directory. """

from os import listdir, rename, remove

files_to_ignore = ['change.py']
directory = "."
oldtext = "is"
newtext = "was"

print "Replacing '%s' with '%s' in directory '%s'." \
	% (oldtext, newtext, directory)
for file in listdir(directory):
	if file in files_to_ignore: continue
	original = file + ".orig"
	rename(file, original)
	input = open(original, "r")
	output = open(file, "w")
	print " Working on '%s'; original saved as '%s'." % (file, original)
	for line in input.readlines():
		newline = line.replace(oldtext, newtext)
		output.write(newline)

#
# Also look at 're' regular expression package.
#   from re import sub
#   newstring = sub( pattern, replacement, string)
# pattern is a regular expression :
#   .    any single character
#   *    any sequence of preceding reg.exp.
#   ()   grouping
#   many other bells and whistles
#