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It's amazing how much crap was included in my homepage when I exported it from the old Emacs Wiki (e.g. Google Analitics, random Spanish ("contenidos")). Cleaning out the junk will be a work in progress.

I guess I’m an addict – even on a Mac, I write my code, read my mail, keep a diary, and even sometimes browse the web in GnuEmacs. I’ve even been known to control iTunes with a bastard child of Emacs and MySQL.

Here are the functions I use to control iTunes: [1]. There is another library out there to do this, but I didn’t know about it at the time.

I am currently developing Sepia, a set of tools to improve interactive Perl development in Emacs, adding things like an interactive mode, find-function, eldoc, and cross-referencing. It now has a manual, and is mostly ready for public consumption.

Some time ago I wrote SimpleCallTree, trying to find bits of unused code in my Perl script. It uses font-lock-function-name to identify function names, so if you’re writing trivial Perl, it might actually work… I’m interested in your code. – AlexSchroeder

Heh – that’s pretty clever. My code is perl-specific, and so probably less interesting, relying on a Perl backend to crawl over the compiled program.

I develop EmacsLispForRuby, talking Emacs with Ruby. I’ll consult Sepia. – rubikitch

I’ve tried el4r, and in most ways, it’s much better than Sepia… though Sepia does have a few of its own tricks. – SeanO

Peeves / Hall of Shame Snippets Peeves / Hall of Shame

When you write Emacs extensions, please use the built-in facilities where possible, as reinvented wheels are annoying. Today’s example, which disables iswitchb in w3m buffers:

   (defun w3m-e21-switch-to-buffer (buffer &optional norecord)
     "Run `switch-to-buffer' and redisplay the header-line.
   Redisplaying is done by wobbling the window size."
     (interactive "BSwitch to buffer: ")
         (switch-to-buffer buffer norecord)
       (when (and header-line-format
                  (eq major-mode 'w3m-mode))


A bit of code I’ve had in my init file for awhile to go to the definition of whatever elisp thing is at point:

   (defun find-thing-at-point (&optional always-ask)
     (interactive "P")
     (let* ((at-point (thing-at-point 'symbol))
            (s (and at-point (intern at-point)))
            (v (or (variable-at-point)
                   (and s (boundp s) s)))
            (f (or (function-called-at-point)
                   (and s (fboundp s) s))))
       (push-mark (point) t)
         (always-ask (call-interactively 'find-function))
         ((and v (not (numberp v)))
          (find-variable v))
         ((and f (subrp (symbol-function f)))
          (let ((buf-pos (find-function-search-for-symbol
                          f nil (help-C-file-name (symbol-function f) 'subr))))
            (and (car buf-pos) (pop-to-buffer (car buf-pos)))))
         (f (find-function f))
         (t (call-interactively 'find-function)))))

Good idea. Based on this, I’ve added a similar command (‘find-fn-or-var-nearest-point’) to Lisp:thingatpt+.el. Thanks. -- DrewAdams

Another bit to jump to a function within the buffer using ido and semantic:

   (defun my-semanticdb-minor-mode-p ()
   "Query if the current buffer has Semanticdb mode enabled."
     (condition-case blah
         (and (semanticdb-minor-mode-p)
              (eq imenu-create-index-function
       (error nil)))
   (defun my-icompleting-read (prompt choices)
     (flet ((ido-make-buffer-list (default)
              (setq ido-temp-list choices)))
       (ido-read-buffer prompt)))
   (defun my-jump-to-function ()
   "Jump to a function found by either Semantic or Imenu within the
   current buffer."
       ((my-semanticdb-minor-mode-p) (my-semantic-jump-to-function))
       ((boundp 'imenu-create-index-function) (my-imenu-jump-to-function))))
   (defun my-imenu-jump-to-function ()
   "Jump to a function found by Semantic within the current buffer
   with ido-style completion."
       (setq imenu--index-alist (funcall imenu-create-index-function)))
     (let ((thing (assoc
                      (my-icompleting-read "Go to: "
                                           (mapcar #'car imenu--index-alist))
       (when thing
         (funcall imenu-default-goto-function (car thing) (cdr thing))
   (defun my-semantic-jump-to-function ()
   "Jump to a function found by Semantic within the current buffer
   with ido-style completion."
     (let ((tags
             (lambda (x)
               (or (getf (semantic-tag-attributes x) :prototype-flag)
                   (not (member (cadr x) '(function variable type)))))
             (semanticdb-file-stream (buffer-file-name (current-buffer)))))
           (names (make-hash-table :test 'equal)))
       (dolist (tag tags)
         (let ((sn (semantic-tag-name tag)))
           (when (gethash sn names)
             (setq sn
                   (loop for i = 1 then (1+ i)
                      for name = (format "%s<%d>" sn i)
                      while (gethash name names)
                      finally return name)))
           (puthash sn tag names)))
       (goto-char (semantic-tag-start
                    (my-icompleting-read "Go to: " (hash-table-keys names))

Great, exactly what I was looking for Unfortunately this results in “Symbol’s function definition is void: hash-table-keys” on Aquamacs 0.99d - any thoughts? JanR?

Oops! This is one of mine:

   (defun hash-table-keys (hash)
     (let ((ret nil))
       (maphash (lambda (k v) (push k ret)) hash)

Also, IMHO you should switch to the normal Carbon Emacs. Aquamacs is a mutant abomination.

Another bit to use Spotlight as a stand-in for locate on OSX:

   (defun spotlight ()
     (let ((locate-command "mdfind"))
       (call-interactively 'locate nil)))

Useful snippet for Perl hackers:

   (defun w3m-about-perldoc-buffer (url &optional no-decode no-cache &rest args)
     "Handle perldoc in the current buffer."
     (when (string-match "\\`about://perldoc-buffer/" url)
       (let ((buf (get-buffer (w3m-url-decode-string
   			    (substring url (match-end 0)))))
   	  (default-directory w3m-profile-directory)
   	  (process-environment (copy-sequence process-environment)))
         ;; To specify the place in which pod2html generates its cache files.
         (setenv "HOME" (expand-file-name w3m-profile-directory))
         (insert-buffer buf)
         (when (zerop (apply #'call-process-region
   			  (point-min) (point-max)
   			  t '(t nil) nil
   			  (append w3m-perldoc-pod2html-arguments
   	(let ((case-fold-search t))
   	  (goto-char (point-min))
   	  (while (re-search-forward
   		  "<a href=\"about://perldoc\\(-buffer\\)?/\\([^\"]*\\)\\(\\.html\\)\">" nil t)
   	    (delete-region (match-beginning 3) (match-end 3))
   	      (narrow-to-region (match-beginning 2) (match-end 2))
   	      (while (search-backward "/" nil t)
   		(delete-char 1)
   		(insert "::"))
   	      (goto-char (point-max))))
   (defun w3m-view-pod (&optional buffer)
     "View POD for the current buffer."
     (w3m-goto-url (concat "about://perldoc-buffer/"
   			(w3m-url-encode-string (buffer-name buffer)))))
   (defun w3m-pod-file (file)
     "View POD for FILE."
       (insert-file file)
        (concat "about://perldoc-buffer/"
                (w3m-url-encode-string (buffer-name (current-buffer)))))))

A generic version of ‘X-other-window’ (specific ‘X-other-window’ functions are usually better):

   (defun make-other-window-map (okmap)
     (unless (eq window-system 'ns)
       (let ((kmap (if (consp okmap) (cadr okmap) okmap)))
           ((consp kmap)
            (let ((ret (make-sparse-keymap)))
              (dolist (kv kmap)
                (define-key ret (car kv) (other-windowize (cdr kv))))
           ((char-table-p kmap)
            (let* ((ret (copy-keymap okmap)))
              (map-char-table (lambda (k v)
                                (unless (keymapp k)
                                  (aset (cadr ret) k (other-windowize v))))
                              (cadr ret))
              (dolist (kv (cddr ret))
                (setf (cdr kv) (other-windowize (cdr kv))))
           (t (error "wtf is this: %s" kmap))))))
   (defun other-windowize (fn)
     `(lambda ()
         (save-window-excursion (call-interactively ',fn) (current-buffer)))))

Go to the indicated line with ‘find-file-at-point’:

   (defadvice find-file-at-point (around goto-line compile activate)
     (let ((line (and (looking-at ".*:\\([0-9]+\\)")
                      (parse-integer (match-string 1)))))
       (and line (goto-line line))))

Awesome, thank you! – RyanDavis

A better way to define hooks, particularly when you’re experimenting with them, than “(add-hook ‘blah (lambda () …))”:

   (defmacro defhook (mode &rest body)
     (let ((name (intern (concat "my-" (symbol-name mode) "-hook"))))
         ',(intern (concat (symbol-name mode) "-hook"))
         (defun ,name ()
        (put ',name 'definition-name ',mode))))
   (put 'defhook 'lisp-indent-function 1)

Since it took me so long to figure this one out (hey, it is late), I thought I’d add an example:

   (defhook text-mode ; note not 'text-mode

– RyanDavis

A function to go to the definition of a function bound to a key; basically, a shortcut for ‘C-h k’, ‘C-x o’, ‘TAB’, ‘RET’:

   (defun my-find-key (k &optional untranslated up-event)
     "Find the definition of a key."
     (interactive "kKey Sequence: \np\nU")
     (if (numberp untranslated)
         (setq untranslated (this-single-command-raw-keys)))
       (let ((modifiers (event-modifiers (aref k 0)))
   	  window position)
         ;; For a mouse button event, go to the button it applies to
         ;; to get the right key bindings.  And go to the right place
         ;; in case the keymap depends on where you clicked.
         (if (or (memq 'click modifiers) (memq 'down modifiers)
   	      (memq 'drag modifiers))
   	  (setq window (posn-window (event-start (aref k 0)))
   		position (posn-point (event-start (aref k 0)))))
         (when (windowp window)
   	    (set-buffer (window-buffer window))
   	(goto-char position))
         (let ((defn (key-binding k)))
           (if (or (null defn) (integerp defn) (equal defn 'undefined))
               (message "%s is undefined" (help-key-description k untranslated))
               (find-function defn))))))

Icicles faces for dark backgrounds:

    '(icicle-complete-input ((((background dark)) nil)))
    '(icicle-completing-mustmatch-prompt-prefix ((((type x w32 mac graphic) (class color)) (:foreground "Cyan"))))
    '(icicle-completing-prompt-prefix ((((type x w32 mac graphic) (class     color)) (:foreground "Red"))))
    '(icicle-current-candidate-highlight ((((background dark)) (:background "gray20"))))
    '(icicle-historical-candidate ((((background dark)) (:foreground "White"))))
    '(icicle-prompt-suffix ((((type x w32 mac graphic) (class color) (background dark)) (:foreground "LightSlateBlue"))))
    '(icicle-search-context-level-1 ((((background dark)) (:background     "gray20" :weight bold))))
    '(icicle-search-context-level-2 ((((background dark)) (:background     "gray15" :weight bold))))
    '(icicle-search-context-level-3 ((((background dark)) (:background     "gray10" :weight bold))))
    '(icicle-search-context-level-4 ((((background dark)) (:weight bold))))
    '(icicle-search-context-level-5 ((((background dark)) (:weight bold))))
    '(icicle-search-context-level-6 ((((background dark)) (:weight bold))))
    '(icicle-search-context-level-7 ((((background dark)) (:weight bold))))
    '(icicle-search-context-level-8 ((((background dark)) (:weight bold))))
    '(icicle-search-current-input ((t (:foreground "green"))))
    '(icicle-search-main-regexp-current ((((background dark)) (:foreground "DodgerBlue"))))
    '(icicle-search-main-regexp-others ((((background dark)) (:foreground     "SeaGreenk"))))
    '(icicle-special-candidate ((((background dark)) (:foreground "yellow"))))
    '(icicle-whitespace-highlight ((t (:background "#300")))))

Current curmudgeon code:

   (blink-cursor-mode		0)
   (tool-bar-mode			0)
   (when (fboundp 'tooltip-mode)
     (tooltip-mode			0))
   (with-current-buffer (get-buffer-create "*scratch*")
     (setq buffer-offer-save nil))
    line-move-visual		nil
    initial-scratch-message	nil)

Prevent the occasional disaster by confirming comint exits:

   (defadvice comint-send-eof (around warn-me-please compile activate)
     "Confirm EOF when called interactively, because accidental EOF sucks."
     (when (or (not (member this-command '(comint-send-eof
               (y-or-n-p "Really exit? "))