Re: Negative Lookahead Equivalent in emacs

[luishenriquezperez]

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.