Don't want to do the regexp test twice

[Egbert Bouwman]

While looping over a long list (with file records)
I use an (also long) if..elif sequence.
One of these elif's tests a regular expression, and 
if the test succeeds, I want to use a part of the match.
Something like this:

pat = re.compile(r'...')
for line in mylist:
    if ... :
        ....
    elif ... :
        ....
    elif pat.search(line):
        mat = pat.search(line)
    elif ... :
       ...
    else ...:
       ...
Is there a way to to do this job with only one pat.search(line) ?
Of course I can do this:

for line in mylist:
    mat = pat.search(line)
    if  ...:
        ....
    elif ...:
        ....
    elif mat:
        ...
but the test is relevant in only a relatively small number of cases.    
And i would like to know if there exists a general solution
for this kind of problem.
egbert

-- 
Egbert Bouwman - Keizersgracht 197 II - 1016 DS  Amsterdam - 020 6257991
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