Re: Check for empty grep and suggest fuzzy grep instead

[Nikolaj Schumacher]

Nordlöw <per.nordlow@gmail.com> wrote:

> How can I check the number of hits grep found (from within Emacs of
> course). I need this in order to auto-suggest a fuzzy grep instead
> somewhat like what happens when you search for a pattern that Google
> doesn't know about.

>From what you want to do, it sounds like you need a combination of "grep
-c" and compilation-finish-functions.

But from you question, it sounds like you want something like this:

(adapted from my package full-ack.el, which is an ack front-end)
(defun grep-count-matches ()
  "Count the matches printed by `grep' in the current buffer."
  ;; Force fontification.
  (font-lock-fontify-region (point-min) (point-max))
  (let ((c 0)
        (beg (point-min)))
    (setq beg (next-single-char-property-change beg 'font-lock-face))
    (while (< beg (point-max))
      (when (eq (get-text-property beg 'font-lock-face) 'match)
        (incf c))
      (setq beg (next-single-char-property-change beg 'font-lock-face)))
    c))


regards,
Nikolaj Schumacher