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Old 09-19-2006, 11:28 AM   #1
dakensta
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Don't match a regular expression


I haven't been able to find this but it must be simple enough ...

Given a regular expression that identifies a text pattern and produces a set of results, how do I change the expression so that it that gives me the complement of that set, i.e. all the lines in the file that do not match my regexp?
 
Old 09-19-2006, 11:40 AM   #2
pete1234
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From man grep:
Quote:
-v, --invert-match
Invert the sense of matching, to select non-matching lines.
 
Old 09-19-2006, 11:47 AM   #3
mjones490
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It would depend on what you are using to process the expression. If you are using grep use the -v (--invert-match) switch. If you are using perl, I believe you can use the !~= operator.

Thanks,
Mark

Last edited by mjones490; 09-19-2006 at 12:37 PM.
 
Old 09-19-2006, 03:09 PM   #4
dakensta
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I am actually doing this in BBEdit, which supports regular expressions, hence wondering if this can be done with a single expression. I guess that Grep is probably the easiest option, from which I can just divert the output to one of the internal buffers (or whatever they call them...) but I will try perl syntax first ... edit: no luck

Thanks.

Last edited by dakensta; 09-19-2006 at 03:13 PM.
 
Old 09-20-2006, 01:09 AM   #5
chrism01
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Perl is
!~
for not match,
=~
for does match
Note that regex engines inside various tools eg bash/awk/grep/perl etc etc are not all the same. See http://www.oreilly.com/catalog/regex/
 
Old 09-20-2006, 03:47 AM   #6
Wim Sturkenboom
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Usually a ^ will take care of negation
Code:
        if(!(ereg("[A-Z]",$data['password']) &&
             ereg("[a-z]",$data['password']) &&
             ereg("[0-9]",$data['password']) &&
             ereg("[^A-Za-z0-9]",$data['password'])))
The last line in this piece of PHP code checks for something not being A-Z,a-z or 0-9 (so matching anything else). This is pure regexp and independent of programming languages or tools.

So your regexp should be like
Code:
[^A-Za-z0-9]
to find i.e. any punctuation, braces etc.
 
Old 09-21-2006, 02:57 AM   #7
chrism01
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FYI, there's a warning about that fn here: http://au.php.net/manual/en/function.ereg.php
 
Old 09-21-2006, 03:48 AM   #8
Wim Sturkenboom
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Hi Chrism01,

sorry, but I don't see the warning. Can you quote part (or all) of it please so I can find it.

PS only find posts from jason denying a possible broken implementation
 
  


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