Elisp on /usr

What's New in Emacs 24.4

Mon, 30 Dec 2013 00:00:00 +0000

Mickey Petersen has written up an excellent round-up of the latest features of the Emacs 24.4 release.

Read the whole article at http://www.masteringemacs.org/articles/2013/12/29/whats-new-in-emacs-24-4/.

He had also written a similar article for Emacs 24.3 (current stable version), which can be found here.

New Settings that I am using

I have already setup the load-prefer-newer, cycle-spacing, and ns-use-srgb-colorspace options.

The new electric-pair-mode options also look interesting, and I have set these up (I was using skeleton-pair for the auto-pairing function till now).

Emacs function to add new path elements to the $PATH environment variable

Wed, 20 Jan 2010 00:00:00 +0000

A very simple eLisp function to add new path elements to the PATH environment variable. Very useful for adding new comint executables from within .emacs/init.el files.

(defun my-add-path (path-element)
"Add the specified path element to the Emacs PATH"
(interactive "DEnter directory to be added to path: ")
(if (file-directory-p path-element)
(setenv "PATH"
(concat (expand-file-name path-element)
path-separator (getenv "PATH")))))

Google Search from within Emacs

Tue, 19 Jan 2010 00:00:00 +0000

A quick and dirty eLisp function for searching on the internet from within Emacs. The default is to search using Google, but you can add to the *internet-search-urls* variable to setup additional search URLs.

By default, the search term is appended at end of the URL - however, you can also encode the specific search term insertion point in the URL by marking the position using the “%s” marker.

;;; The custom search URLs
(defvar *internet-search-urls*
(quote ("http://www.google.com/search?ie=utf-8&oe=utf-8&q=%s"
"http://en.wikipedia.org/wiki/Special:Search?search=")))
;;; Search a query on the Internet using the selected URL.
(defun search-in-internet (arg)
"Searches the internet using the ARGth custom URL for the marked text.
If a region is not selected, prompts for the string to search on.
The prefix number ARG indicates the Search URL to use. By default the search URL at position 1 will be used."
(interactive "p")
;; Some sanity check.
(if (> arg (length *internet-search-urls*))
(error "There is no search URL defined at position %s" arg))
(let ((query                          ; Set the search query first.
(if (region-active-p)
(buffer-substring (region-beginning) (region-end))
(read-from-minibuffer "Search for: ")))
;; Now get the Base URL to use for the search
(baseurl (nth (1- arg) *internet-search-urls*)))
;; Add the query parameter
(let ((url
(if (string-match "%s" baseurl)
;; If the base URL has a %s embedded, then replace it
(replace-match query t t baseurl)
;; Else just append the query string at end of the URL
(concat baseurl query))))
(message "Searching for %s at %s" query url)
;; Now browse the URL
(browse-url url))))

Quickly diff the changes made in the current buffer with its file

Tue, 19 Jan 2010 00:00:00 +0000

Update (23rd Jan 2010): Separated the key-assignment and function definition.

A simple function to quickly do a diff of the current buffer contents with its underlying file. Very useful if the file has been changed outside (e.g., a log file).

;; Diff the current buffer with the file contents
(defun my-diff-current-buffer-with-disk ()
 "Compare the current buffer with it's disk file."
(interactive)
 (diff-buffer-with-file (current-buffer)))
(global-set-key (kbd "C-c w") 'my-diff-current-buffer-with-disk)