From: luishenriquezperez@gmail.com
To: help-gnu-emacs@gnu.org
Subject: Re: Negative Lookahead Equivalent in emacs
Date: Wed, 10 May 2017 08:51:25 -0700 (PDT) [thread overview]
Message-ID: <6f43469f-663e-4a7f-9811-384a43b2611a@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.
I edited the solution slightly so no new lines are included.
\[^[:space:]\n\]\\(?:\[[:space:]\]\\|$\\)
There are a lot of backslashes because I used regex-builder to test it.
prev parent reply other threads:[~2017-05-10 15:51 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
2017-05-10 1:41 ` Emanuel Berg
2017-05-10 15:51 ` luishenriquezperez [this message]
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