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From: luishenriquezperez@gmail.com
To: help-gnu-emacs@gnu.org
Subject: Re: Negative Lookahead Equivalent in emacs
Date: Tue, 9 May 2017 06:50:54 -0700 (PDT)	[thread overview]
Message-ID: <724011cf-c6d3-45a5-889e-0c94be91cfbc@googlegroups.com> (raw)
In-Reply-To: <49e1dd7d-4be5-4b03-b9e2-e26b15b0a6cb@googlegroups.com>

On Tuesday, May 9, 2017 at 1:15:46 AM UTC-4, luishenri...@gmail.com wrote:
> Hi,
> 
> I'm trying to write a regex that matches the last character of a sequence of non-whitespace characters '[^\n\r\t\f ]', or an empty line matching ^$. 
> 
> Thus: 
> Hello World! --> "o" and "!" would be matched
> 
> In non-elisp regex languages I know the code for this is: \S(?!\S) 
> I know that \S is equivalent too [^ /n/r/t/f]. 
> But I'm unsure of what the elisp equivalent (if any) of the negative lookahead (?!).
> 
> I saw on this forum a post  "gnu.emacs.help › regex nirvana - near miss"
> Where Drew Adams said: "Typically, what you want to do for this in Emacs Lisp is to combine 
> the use of a regexp for positive matching with other code that takes 
> care of the non-matching (negation) need. "
> 
> However, I'm not sure how to go about doing this.

Thank you this worked out.


  parent reply	other threads:[~2017-05-09 13:50 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-05-09  5:15 Negative Lookahead Equivalent in emacs luishenriquezperez
2017-05-09  7:16 ` Emanuel Berg
2017-05-09  8:44 ` hector
2017-05-09  9:54 ` Wasell
2017-05-10 14:23   ` luishenriquezperez
2017-05-09 10:03 ` Felix Dietrich
2017-05-09 13:50 ` luishenriquezperez [this message]
2017-05-10  1:41   ` Emanuel Berg
2017-05-10 15:51 ` luishenriquezperez

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