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Help with regular expression

I'm trying to write an RE to match a string that might or might not be
ther and everything past it up to another string that might or might not
be there and everything past it to a third string that might or might
not be there and everything past it.

Say my strings are "STRING1", "STRING2", and "String3".

Would the re be:

r'((STRING1.*)( STRING2.*)(STRI NG3.*))'

The goal is to separate the groups by newlines, but I only want the
first group to match up to the second group and the second to match up
to the third.

Normally I would achieve this by typing:

pat = re.compile(r'(( STRING1.*)(STRI NG2.*)(STRING3. *))')
m = pat.findall(s)
s = '\n\n'.join(m[0])

but the first group would seem to match everything.

How can I get it to do what I want?

-- Stephen

Jul 18 '05 #1
2 1221
Stephen Boulet wrote:
I'm trying to write an RE to match a string that might or might not be
ther and everything past it up to another string that might or might not
be there and everything past it to a third string that might or might
not be there and everything past it.

Say my strings are "STRING1", "STRING2", and "String3".

Would the re be:

r'((STRING1.*)( STRING2.*)(STRI NG3.*))'

The goal is to separate the groups by newlines, but I only want the
first group to match up to the second group and the second to match up
to the third.

Normally I would achieve this by typing:

pat = re.compile(r'(( STRING1.*)(STRI NG2.*)(STRING3. *))')
m = pat.findall(s)
s = '\n\n'.join(m[0])

but the first group would seem to match everything.

How can I get it to do what I want?

-- Stephen


Try non-greedy wildcards: r'((STRING1.*?) (STRING2.*?)(ST RING3.*?))'
- - -

should do the trick.

hth,
anton.

Jul 18 '05 #2
"anton muhin" <an************ *************** *****@rambler.r u> schrieb im
Newsbeitrag news:bk******** ***@news.peterl ink.ru...
Stephen Boulet wrote:
I'm trying to write an RE to match a string that might or might not be
ther and everything past it up to another string that might or might not
be there and everything past it to a third string that might or might
not be there and everything past it.


Try non-greedy wildcards: r'((STRING1.*?) (STRING2.*?)(ST RING3.*?))'
- - -


Since you said that each of the three strings might or not be there you
would need:

r'((STRING1.*?) ?(STRING2.*?)?( STRING3.*?)?)'

Ciao Ulrich
Jul 18 '05 #3

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