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From: Stefan Monnier <monnier@iro.umontreal.ca>
Newsgroups: gmane.emacs.help
Subject: Re: how to make next-error work on non-grep non-compilation
Date: Fri, 20 May 2011 13:20:24 -0300
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> (defun skill-vlint-present (file-name)
>   (let (size
>         (vlint (get-buffer-create "vlint")))
>     (with-current-buffer vlint
>       (let ((inhibit-read-only t))
>         (erase-buffer)
>         (insert-file-contents-literally file-name)
>         (when (setq size (- (point-max) (point-min)))
>           (grep-mode))))
>     (when (plusp size)
>       (switch-to-buffer-other-window vlint))))

Looks much better than the code you sent before.  Note that 0 when
interpreted as a boolean in Elisp is the same as true, so the
"(when (setq size (- (point-max) (point-min)))" will always call the
`grep-mode'.  And you can use (buffer-size) instead of (- (point-max)
(point-min)).  Oh, and I'd use (unless (zerop size)...) since `plusp' is
not standard Elisp but only provided by the CL library.


        Stefan