NotJava.py

from functools import reduce
from operator import add

#Doesn't handle whitespace padding well
def countWords(s):
	return len(s.split(' '))

def stopLooping():
	global looping 
	looping = False
	print('Bye!')

def wordsInLine():
	s = input('Line? ')
	print('You typed %s words\n' % countWords(s))

def readFile():
	global lines
	filename = input('Filename? ')
	try:
		with open(filename, 'r') as f:
			lines = f.readlines()
	except IOError as e:
		print(str(e))
		return
	print('There are %s lines in %s.' % (len(lines), filename))

def writeFile():
	if lines is None:
		print('You should try option 2 first.')
		return
	filename = input('Filename? ')
	lengths = [countWords(line) for line in lines]
	with open(filename, 'w') as f:
		for pair in zip(lengths, lines):
			f.write('%03d %s' % pair)
	print('There are %s words in %s' % (reduce(add, lengths, 0), filename))

looping = True
lines = None

def main():
	menu = {'0' : ('Exit', stopLooping), 
	        '1' : ('Count words in a line.', wordsInLine),
	        '2' : ('Read the file into memory.', readFile),
	        '3' : ('Write a numbered file.', writeFile) }

	while looping:
		for num, (label, _) in sorted(menu.items()):
			print('%s) %s' % (num, label))
		print()
		user_in = input('> ')
		if user_in in menu:
			menu[user_in][1]()
		else:
			print('Sorry, not an option.')
		print('')

if __name__ == '__main__':
	main()