It is highly probably that
re.finditer(link) uses fairly minimal memory overhead.
def split_iter(string): return (x.group(0) for x in re.finditer(r"[A-Za-z']+", string))
>>> list( split_iter("A programmer's RegEx test.") ) ['A', "programmer's", 'RegEx', 'test']
edit: I have just confirmed that this takes constant memory in python 3.2.1, assuming my testing methodology was correct. I created a string of very large size (1GB or so), then iterated through the iterable with a
for loop (NOT a list comprehension, which would have generated extra memory). This did not result in a noticeable growth of memory (that is, if there was a growth in memory, it was far far less than the 1GB string).