# Regular Expressions

'''
Basics:

sub - replaces a given pattern with something within a string, returns the result
match - returns a match object if a pattern is found in a string... useful for testing for matches
'''

import re

# from Gulliver's Travels by Jonathan Swift (Part III, Chapter II)
text = '''
After he had left me, I placed all my words, with
their interpretations, in alphabetical order.  And thus, in a few
days, by the help of a very faithful memory, I got some insight
into their language.  The word, which I interpret the flying or
floating island, is in the original Laputa, whereof I could never
learn the true etymology.  Lap, in the old obsolete language,
signifies high; and untuh, a governor; from which they say, by
corruption, was derived Laputa, from Lapuntuh.  But I do not
approve of this derivation, which seems to be a little strained.  I
ventured to offer to the learned among them a conjecture of my own,
that Laputa was quasi lap outed; lap, signifying properly, the
dancing of the sunbeams in the sea, and outed, a wing; which,
however, I shall not obtrude, but submit to the judicious reader.
'''

# we'll transform the text into a bare-bones string with words only and no punctuation

# we don't care about punctuation
text = re.sub("[^\w]", " ", text)

# nor do we care about case
text = text.lower()

# we might now have lots of whitespace--we only want spaces
text = re.sub("\s+", " ", text)

# get rid of any whitespace at the beginning and end of the string
text = text.lstrip()
text = text.rstrip()

print text