[Tutor] Issues with regex escaping on \{

[vince spicer]

On Wed, Jul 29, 2009 at 11:35 AM, gpo <goodpotatoes at yahoo.com> wrote:

>
> My regex is being run in both Python v2.6 and v3.1
> For this example, I'll give one line.  This lines will be read out of log
> files.  I'm trying to get the GUID for the User ID to query a database with
> it, so I'd like a sub match.  Here is the code
> -----------------
> import re
> line = '>Checking Privilege for UserId:
> {88F96ED2-D471-DE11-95B6-0050569E7C88}, PrivilegeId:
> {71AD2527-8494-4654-968D-FE61E9A6A9DF}. Returned hr = 0'
> pUserID=re.compile('UserID: \{(.+)\}',re.I)  #Sub match is one or more
> characters between the first set of squigglies immediately following
> 'UserID: '
>
> #the output is:
> (re.search(pUserID,line)).group(1)
> '88F96ED2-D471-DE11-95B6-0050569E7C88}, PrivilegeId:
> {71AD2527-8494-4654-968D-FE61E9A6A9DF'
> -----------
> Why isn't the match terminating after it finds the first \}  ?
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your grouping (.+) appears to be greedy, you can make it non-greedy with a
question mark

EX:

pUserID=re.compile('UserID:\s+{(.+?)}',re.I)

Vince
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