[Tutor] Question regular expressions - the non-greedy pattern

Mon Jan 21 15:45:05 CET 2013

Hello,

in the howto (http://docs.python.org/2/howto/regex.html#regex-howto)
there are code examples near the end of the page  (the non-greedy
pattern) I am referring to:

s = '<html><head><title>Title</title>'
>>> len(s)
32
>>> print re.match('<.*>', s).span()
(0, 32)
>>> print re.match('<.*>', s).group()
<html><head><title>Title</title>

print re.match('<.*?>', s).group() #<- I'm referring to this
<html>

So far everything is fine.

Now I'm changing the input string to (adding an extra '<'):

s = '<<html><head><title>Title</title>'

and evoking the last command again:

print re.match('<.*?>', s).group()
I would expect to get the same result

<html>

as I'm using the non-greedy pattern. What I get is

<<html>

Did I get the concept of non-greedy wrong or is this really a bug?
I've treid this with
python -V
Python 2.7.3
on Win 7 64 Bit as well as Ubuntu 64 bit.

I'd be glad to here from you soon.

Thank's a lot for your effort.

best regards

Marcin