isearch-yank-word-at-point (was Re: Key map translations)

[Christoph Scholtes <cschol2112@googlemail.com>]

On 4/13/2011 1:07 AM, Deniz Dogan wrote:

> This is something I've been wanting for a long time but never really
> realized it. Is there really nothing similar in isearch already? Maybe
> we could add it?

I reworked my function a little and the interface is slightly different. 
You press `C-s' to enter isearch mode and then `C-a' to select the 
entire word at point, much like `C-w' would select the word from point 
on. `Word' is in this case defined as a sequence of word and symbol 
constituents.

Here is the code:

(defun isearch-yank-word-at-point ()
   "Pull word at point into the search string."
   (interactive)
   ;; Only yank if point is on a word constituent or
   ;; symbol constituent per the syntax table.
   (when (or (= (char-syntax (or (char-after) 0)) ?w)
             (= (char-syntax (or (char-after) 0)) ?_))
     ;; If part of the string has been yanked to the search string
     ;; already, unwind the isearch state stack to the beginning to
     ;; start over.
     (while (not (string= isearch-string ""))
       (isearch-pop-state))

     ;; Go to beginning of word at point
     (skip-syntax-backward "w_")
     ;; and yank entire word into search string.
     (isearch-yank-internal
      (lambda ()
        (skip-syntax-forward "w_")
        (point)))))


I bind the command as follows:

(define-key isearch-mode-map (kbd "C-a") 'isearch-yank-word-at-point)

Feedback welcome. I would be happy to add this to isearch.el if people 
find it useful.

Christoph