re_search_substring.py

#!/usr/bin/env python


import re

text = 'This is some text -- with punctuation.'
pattern = re.compile(r'\b\w*is\w*\b')

print 'Text:', text
print

pos = 0
while True:
    match = pattern.search(text, pos)
    if not match:
        break
    s = match.start()
    e = match.end()
    print ' %2d : %2d = "%s"' % \
        (s, e - 1, text[s:e])
    # move forward in text for the next search
    pos = e