Groups > comp.lang.java.programmer > #28561

Re: regex tidy

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From	Joshua Cranmer 🐧 <Pidgeot18@verizon.invalid>
Newsgroups	comp.lang.java.programmer
Subject	Re: regex tidy
Date	Sun, 25 May 2014 13:31:31 -0500
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On 5/25/2014 11:21 AM, Roedy Green wrote:
> On Sat, 24 May 2014 14:55:03 +0200, Robert Klemme
> <shortcutter@googlemail.com> wrote, quoted or indirectly quoted
> someone who said :
>
>>> 7. use negative char lists when it would shorten the list.
>>
>> I don't believe this has any impact as this is something the regex
>> engine will do internally.
>
> I was thinking of a transform something like one that searched for
> every character but " by specifying every ascii char but one. It could
> be simplified to use a negative.  Perhaps the author had never heard
> of negative searches.

That wouldn't be correct. The original regex would not match, e.g., Õ, 
while your converted one would.

[Although this does raise the question of how regular expressions handle 
or fail to handle characters like 💩 or the penguin in my display name. 
Stupid UTF-16 and the "it's fixed-width characters if you look at it 
funny" results.]

-- 
Beware of bugs in the above code; I have only proved it correct, not 
tried it. -- Donald E. Knuth

Thread

regex tidy Roedy Green <see_website@mindprod.com.invalid> - 2014-05-23 11:39 -0700
  Re: regex tidy leif.roar@invalid.com (Leif Roar Moldskred) - 2014-05-23 14:33 -0500
    Re: regex tidy Joshua Cranmer 🐧 <Pidgeot18@verizon.invalid> - 2014-05-23 15:05 -0500
  Re: regex tidy Robert Klemme <shortcutter@googlemail.com> - 2014-05-24 14:55 +0200
    Re: regex tidy Roedy Green <see_website@mindprod.com.invalid> - 2014-05-25 09:09 -0700
      Re: regex tidy Robert Klemme <shortcutter@googlemail.com> - 2014-05-25 18:49 +0200
        Re: regex tidy leif.roar@invalid.com (Leif Roar Moldskred) - 2014-05-25 12:28 -0500
          Re: regex tidy Robert Klemme <shortcutter@googlemail.com> - 2014-05-25 19:55 +0200
          Re: regex tidy "Chris Uppal" <chris.uppal@metagnostic.REMOVE-THIS.org> - 2014-05-26 12:12 +0100
    Re: regex tidy Roedy Green <see_website@mindprod.com.invalid> - 2014-05-25 09:10 -0700
    Re: regex tidy Roedy Green <see_website@mindprod.com.invalid> - 2014-05-25 09:13 -0700
    Re: regex tidy Roedy Green <see_website@mindprod.com.invalid> - 2014-05-25 09:21 -0700
      Re: regex tidy Joshua Cranmer 🐧 <Pidgeot18@verizon.invalid> - 2014-05-25 13:31 -0500
        Re: regex tidy "Chris Uppal" <chris.uppal@metagnostic.REMOVE-THIS.org> - 2014-05-26 12:31 +0100

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