Need help with a regular expression

[Sharun]

Python newbie here. I am not clear about how the matching is taking
place when I do the following

str5 = 'aaa bbb\r\n ccc ddd\r\n eee fff'
re5=re.compile('aaa.*(ddd|fff)',re.S);
re5.search(str5).group(0)

'aaa bbb\r\n ccc ddd\r\n eee fff'

re5.search(str5).group(1)

'fff'

I am trying to find the substring starting with 'aaa', and ending with
ddd OR fff. If ddd is found shouldnt the search stop? Shouldn't
re5.search(str5).group(0) return 'aaa bbb\r\n ccc ddd' ?

Thanks

 

[marek.rocki]

I am trying to find the substring starting with 'aaa', and ending with
ddd OR fff. If ddd is found shouldnt the search stop? Shouldn't
re5.search(str5).group(0) return 'aaa bbb\r\n ccc ddd' ?

The documentation for the re module (http://docs.python.org/lib/re-
syntax.html), tells you that the "*", "+", and "?" qualifiers are all
greedy; they match as much text as possible. What you are looking for
are the qualifiers "*?", "+?", "??". Your regex pattern might look
like this: "aaa.*?(ddd|fff)".

Regards,
Marek

 

[Paddy]

Python newbie here. I am not clear about how the matching is taking
place when I do the following


'aaa bbb\r\n ccc ddd\r\n eee fff'


'fff'

I am trying to find the substring starting with 'aaa', and ending with
ddd OR fff. If ddd is found shouldnt the search stop? Shouldn't
re5.search(str5).group(0) return 'aaa bbb\r\n ccc ddd' ?

Thanks

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- Paddy.

 

[Sharun]

Thanks Marek!