RE Module

[tobiah]

> In python's RE module, they're like Perl:
> 
> Greedy:  "<.*>"
> Nongreedy:  "<.*?>"
> 

Oh, I have never seen that.  In that case, why
did Roman's first example not work well for
HTML tags?

'<.*?>'

Also, how does the engine decide whether I am adjusting
the greed of the previous operator, or just asking
for another possible character?

Suppose I want:

	"x*?" to match "xxxxxxxO"

If the '?' means non greedy, then I should get 'x' back.
If the '?' means optional character then I should get
the full string back.

Checking in python:

######################################
import re

s = 'xxxxxxx0'

m = re.search("x*", s)
print "First way", m.group(0)

m = re.search("x*?", s)
print "Second way", m.group(0)
#####################################
First way xxxxxxx
Second way

So now I'm really confused.  It didn't do a non-greedy
'x' match, nor did it allow the '?' to match the '0'.


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