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April 25th, 2008, 09:18 AM

skeeter144

Contributing User

Join Date: Apr 2006

Posts: 30

Time spent in forums: 10 h 51 m 50 sec
Reputation Power: 3

Regex Loop

Data file contains:

Code:

age     : 35
name    : Bob

age     : 22
name    : Bill

Python Code:

Original - Python Code
#!/usr/bin/python import re data = open('./data') data = data.read() output = re.search(r"(?<=name).*", data).group().split(':') output = output[1].strip() print output

 
#!/usr/bin/python
import re
 
data = open('./data')
data = data.read()
output = re.search(r"(?<=name).*", data).group().split(':')
output = output[1].strip()
print output

This outputs:

Code:

Bob

But, if I try and loop through it to match both names:

Python Code:

Original - Python Code
#!/usr/bin/python import re data = open('./data') data = data.read().split('\n') for x in data: name = re.search(r"(?<=name).*", x).group().split(':') print name

 
#!/usr/bin/python
import re
 
data = open('./data')
data = data.read().split('\n')
 
for x in data:
        name = re.search(r"(?<=name).*", x).group().split(':')
        print name

This returns:

Code:

AttributeError: 'NoneType' object has no attribute 'group'

I am pretty sure it's making a match, because I can get:

Code:

None
<_sre.SRE_Match object at 0xb7eaaf38>
None
None
<_sre.SRE_Match object at 0xb7eaaf38>
None
None

Is this not the proper way to try and loop through the matches?

Thanks

April 25th, 2008, 11:11 AM

bvdet

Registered User

Join Date: Mar 2008

Posts: 20

Time spent in forums: 7 h 39 m 4 sec
Reputation Power: 0

The AttributeError speaks for itself. I would suggest something like this:

Python Code:

Original - Python Code
import re data = ''' age : 35 name : Bob age : 22 name : Bill ''' for x in data.split('\n'): m = re.search(r"name\s:\s(.*)", x) if m: print m.group(1)

import re
 
data = '''
age     : 35
name    : Bob
age     : 22
name    : Bill
'''
 
for x in data.split('\n'):
    m = re.search(r"name\s*:\s*(.*)", x)
    if m:
        print m.group(1)

The following will loop over the string without splitting:

Python Code:

Original - Python Code
idx = 0 patt = re.compile(r"name\s:\s(.*)") while True: m = patt.search(data, idx) if m: print m.group(1) idx = m.end() else: break

idx = 0
patt = re.compile(r"name\s*:\s*(.*)")
while True:
    m = patt.search(data, idx)
    if m:
        print m.group(1)
        idx = m.end()
    else:
        break

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