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Python re.findall inverse Match

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# 1  
Old 01-27-2016
Python re.findall inverse Match
I ask of you but yet another simplistic question that I hope can be answered. Its better explained showing my code. Here is my list(tmp_pkglist), which contains a list of all Debian (Jessie) packages:
snippet
Code:
 'zssh (1.5c.debian.1-3.2+b1 [s390x], 1.5c.debian.1-3.2 [amd64, arm64, armel, armhf, i386, mips, mipsel, powerpc, ppc64el])',
 'zsync (0.6.2-1)',
 'ztex-bmp (20120314-2)',
 'zurl (1.3.1-4)',
 'zutils (1.3-4)',
 'zutils-dbg (1.3-4) utilities for dealing with compressed files transparently (debug)',
 'zvbi (0.2.35-3) Vertical Blanking Interval (VBI)',
 'zygrib (6.2.3-1)',
 'zygrib-maps (6.2.3-1)',
 'zynadd (1+git.20100609+dfsg0-2)',
 'zynaddsubfx (2.4.3-4)',
 'zynaddsubfx-dbg (2.4.3-4)',
 'zynaddsubfx-dssi (2.4.3-4)',
 'zypper (1.11.13-1)',
 'zypper-common (1.11.13-1) command line software manager using libzypp (common files)',
 'zypper-doc (1.11.13-1) command line software manager using libzypp (documentation)',
 'zziplib-bin (0.13.62-3)',
 'zzuf (0.13.svn20100215-4.1+b1 [s390x], 0.13.svn20100215-4.1 [amd64, arm64, armel, armhf, i386, mips, mipsel, powerpc, ppc64el])']

Using this block of code and using re.findall, how can I tell the regex to "not" or inversely find all of the lines that do not contain:
Code:
 'zssh (1.5c.debian.1-3.2+b1 [s390x], 1.5c.debian.1-3.2 [amd64, arm64, armel, armhf, i386, mips, mipsel, powerpc, ppc64el])
'zzuf (0.13.svn20100215-4.1+b1 [s390x], 0.13.svn20100215-4.1 [amd64, arm64, armel, armhf, i386, mips, mipsel, powerpc, ppc64el])']

I tried various combos but cannot get the inverse of what I want which is:
Code:
 'zypper (1.11.13-1)',
 'zypper-common (1.11.13-1) command line software manager using libzypp (common files)',
 'zypper-doc (1.11.13-1) command line software manager using libzypp (documentation)',
 'zziplib-bin (0.13.62-3)',

For example:
Code:
for scrape in tmp_pkglist:
            capture = re.findall('?!(.*\[s390x\].*))', scrape)
            if capture:
                    print capture

I am used to using "!" or boolean "not" but have never done it using Pythons "re" module. Thanks in advance.

---------- Post updated at 11:49 AM ---------- Previous update was at 10:44 AM ----------

This did the trick:
Code:
for scrub_norm in tmp_pkglist:
    sanitize_norm = re.findall('.*\[s390x\].*', scrub_norm)
    if not sanitize_norm:
        print scrub_norm

Thanks to grail from antother forum
# 2  
Old 02-01-2016
From the docs at https://docs.python.org/3/library/re.html

Quote:
(?!...)Matches if ... doesn’t match next. This is a negative lookahead assertion. For example, Isaac (?!Asimov) will match 'Isaac ' only if it’s not followed by 'Asimov'.
Or, if you don't care what langauge is used, just pipe a grep -v like the following:

Code:
$ apt-cache search foo | grep -v bar

# 3  
Old 02-01-2016
Quote:
Originally Posted by metallica1973
...I am used to using "!" or boolean "not" but have never done it using Pythons "re" module. ...
Yes, Python uses the more verbose "not" instead of "!" for negative regex matches.

Code:
$
$ cat pkg_list.txt
'zssh (1.5c.debian.1-3.2+b1 [s390x], 1.5c.debian.1-3.2 [amd64, arm64, armel, armhf, i386, mips, mipsel, powerpc, ppc64el])',
'zsync (0.6.2-1)',
'zzuf (0.13.svn20100215-4.1+b1 [s390x], 0.13.svn20100215-4.1 [amd64, arm64, armel, armhf, i386, mips, mipsel, powerpc, ppc64el])']
'ztex-bmp (20120314-2)',
$
$ cat -n negative_match.py
     1  #!/usr/bin/python
     2  import re
     3  input_file = "pkg_list.txt"
     4  for line in open(input_file):
     5      if not re.match('.*\[s390x\].*', line):
     6          print line,
     7
$
$ python negative_match.py
'zsync (0.6.2-1)',
'ztex-bmp (20120314-2)',
$
$

For reference, here's the corresponding regex in Perl:

Code:
$
$ perl -lne 'print if !/\[s390x\]/' pkg_list.txt
'zsync (0.6.2-1)',
'ztex-bmp (20120314-2)',
$
$ perl -lne 'print if not /\[s390x\]/' pkg_list.txt
'zsync (0.6.2-1)',
'ztex-bmp (20120314-2)',
$
$

This User Gave Thanks to durden_tyler For This Post:
Azrael
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