Outline mode (org-mode) is nice, but i never took the time to learn the details. Have been using it simply by just knowing the star header syntax and Tab or Shift Tab to show/hide headings. Today, i took the time and learned the basics keyboard shortcuts for creating and moving branches. Fantastic. Added to Writing Outline with Emacs (org mode tutorial).

Learned a tip today. There's glasses-mode, a minor mode, bundled in at least emacs 22.2. It will display “camelCase” words like this “camel-Case”. Note: it only display it that way, the text is actually not changed. (via gnu.emacs.help post by Tim X)

This tip is added to: Emacs Advanced Tips.

In the past few days, been working on my site that heavily involves emacs lisp scripts i've written.

First is a update to my kml files. See: (Google Earth) KML Validation Fuckup. This involves also updating my script for generating kml files, see: Emacs Lisp: Writing a google-earth Function. Then, i created a collection of links to kml files. See: Google Earth Files at XahLee.org. This is done by modifying my elisp script that generate Wikipedia links. See: Generate a Web Links Report with Emacs Lisp.

ErgoEmacs mentioned in news.ycombinator.com.

Want the cursor movement to stop between camelCaseLetters? Use “global-subword-mode” or “subword-mode”. (Thanks to Deniz Dogan for the tip.)

This tip is added to: Emacs Advanced Tips.

A new version of bbcode-mode. Also a new version of xub Unicode Browser mode.

Spend 8 hours rewrote the article: How To Create Keybinding In Mac OS X. Also, created a system wide ErgoEmacs keybinding for OS X and bash, for both Qwerty and Dvorak layout. Download at: code.google.com. (Thanks to Brendan Miller for the initial work on bash binding)

Also, wrote another article: Keyboard Ghosting; How Many Keys Your Keyboard Can Take?.

A few new articles i wrote in the past few days on keyboarding that might be of interest to emacs users.

• Kinesis Contoured Keyboard Review and RSI
• The Idiocy of Hacker Keyboards
• Keyboard Shortcut Design: Dedicated keys, Special Buttons, Extra Keys

ErgoEmacs 1.8.1 for Windows is out! This one is based on the shiny new Emacs 23.2. (See: Emacs 23.2 Features.) Check it out! Download at: googlecode.com ErgoEmacs 1.8.1 Setup.exe. (Thanks to David Capello for the C coding on Windows.)

Discovered a great tip to copy current line, or cut.

Last month, i wrote Emacs: Shortcut to Delete Whole Line, because i find that deleting whole line is much frequently needed. But also, i didn't mention that i often find the need to copy the current line too. Usually, this meas moving the cursor to beginning of line, mark, move to end of line, then copy. This is 4 operations. The following code will make it just a single operation:

(defadvice kill-ring-save (before slick-copy activate compile)
  "When called interactively with no active region, copy the current line."
  (interactive
   (if mark-active
       (list (region-beginning) (region-end))
     (progn
       (message "Current line is copied.")
       (list (line-beginning-position) (line-end-position)) ) ) ))

(defadvice kill-region (before slick-copy activate compile)
  "When called interactively with no active region, cut the current line."
  (interactive
   (if mark-active
       (list (region-beginning) (region-end))
     (progn
       (message "Current line is cut.")
       (list (line-beginning-position) (line-end-position)) ) ) ))

With the above code, when you do not have a text selection, copy will just copy the current line. Similar for cut. Super!

Thanks to Joseph O'Donnell for mentioning this. The code is originally from emacswiki.org SlickCopy. Apparently, this behavior is default in VisualStudio, TextMate, SlickEdit.

A new convenient elisp function.

Sometimes you want to delete the file of the current buffer. How do you do it? Here's a simple command that does it.

(defun delete-current-file ()
  "Delete the file associated with the current buffer."
  (interactive)
  (let (currentFile)
    (setq currentFile (buffer-file-name))
    (when (yes-or-no-p (concat "Delete file: " currentFile))
      (kill-buffer (current-buffer))
      (delete-file currentFile)
      (message (concat "Deleted file: " currentFile))
      ) ) )

This is also a very simple command to learn elisp. The code is very easy to understand. For more simple examples, see: Emacs Lisp Examples.

Another little emacs tip. The tip is about how to edit files that requires admin privilege.

Often, you want to edit a file that requires admin privilege. So, either you start another emacs instance as root, or, modify the file's permission first with sudo then edit then modify it back. Both solutions are painful.

Starting another emacs instance is slower, and you also need to navigate to the dir path. Edit permission bits is error prone and dangerous.

When i was a full time unix sys admin, i usually always keep a instance of emacs as root, with different colored background. But this is also not a optimal solution.

Here's one short tip from the web:

; from newsgroup gnu.emacs.help, by Richard Riley, 2009-08-02 
(defun open-current-file-as-admin ()
  "Open the current buffer as unix root.
This command works on unixes only."
  (interactive)
  (when buffer-file-name
    (find-alternate-file
     (concat "/sudo:root@localhost:"
           buffer-file-name))))

PS the above works in unixes only (including linuxes and Mac OS X). How does one do on Windows? If you know, please post! Concrete solution that you actually use is preferred.

Little tips about calculating dates.

I needed to find the date of 2010-04-17 minus 200 days. How do you do it in emacs?

Start calendar mode by tying “Alt+x cale Enter”. In calendar mode, the left arrow moves you back. But it also takes a universal argument of n to go back n days. So, type “C-u 200 ←” will put you 200 days back.

When your cursor is in the calender pane, there are these new menus: Scroll, Goto, Holidays, Diary, Sun/Moon. Check them out! I've been using emacs for 12 years, but never realized this!

PS thanks to people on comp.emacs, in particular Jason Rumney.

Some of my emacs lisp tutorial have been translated to Chinese and Japanese.

• Emacs Lisp Idioms in Japanese: 武蔵の日記 (Musashi's Diary) (2009-01-18), By 武蔵, at Source
• Emacs Lisp Basics in Chinese: [elisp]EmacsLisp 基础 (2010-01-31), By laihj, at Source

Thanks people.

This article shows you a quick way to organize your emacs init file.

Most emacs users, has tens or hundred lines in their emacs init file, accumulated over the years. Large emacs init files makes emacs startup slow, and is a problem when you upgrade emacs, or install a new package.

So, how do you organize it? When it comes to organization, most of us, probably thinks of lots of times spend on it, or with some special principle, system, to keep the .emacs file clean. Personally, i find that elaborate rule or system or time spend on this is actually not productive.

...

Learned a new command: “dired-jump”.

If you have a file open and you need to go to the directory the file is in, you can just call dired-jump, and it'll take you to the dir and place your cursor on the file.

You could just use find-file (C-x C-f) then press Enter, because that opens the current dir and the current dir is usually the dir the file is in. However, if the dir has a hundred files, then you have to do a search command to locate the file. The “dired-jump” does all this for you.

In the past, i actually defined my own command for this:

; DON'T USE THIS COMMAND. use dired-jump instead.
(defun show-file-in-dired ()
  "Show the current file in dired.
DON'T USE THIS COMMAND. This command was written before i knew dired-jump."
  (interactive)
  (let (fname dname)
    (setq fname buffer-file-name)
    (setq dname (file-name-directory fname) )
    (dired dname)
    (search-forward (file-name-nondirectory fname))
    )
  )

If typing “dired-jump” is too much for you, you can define a alias “(defalias 'dj 'dired-jump)”, or a shortcut (See: How to Define Keyboard Shortcuts in Emacs).

A new version of AutoHotKey Mode For Emacs is out. This version fixes a defect where if the source code contains “"C:\"”, then everything after is badly syntax colored.

A new report. This report is a major update from the one in 2007, with data size that's 20 times larger. It took some 16+ hours to do this report, most time is spent on thinking and rewriting the python script that generates the report. (i thought it was just gonna be some 2 hours)

A new release of ErgoEmacs is out, at version 1.7. (Thanks to David Capello)

If your are running Microsoft Vista, and you use emacs to edit files in the “C:\Program Files\” or “c:\Program Files (x86)\” dir, and without admin privilege, Windows will automatically create them in “$HOME\AppData\Local\VirtualStore\”. This may be very confusing, because dired will show a certain file you have in the program dir, but it doesn't exist when you use shell to look for it. For detail, see File Aliases Considered A Plague.

Sometimes, i want take out all the syntax coloring of some text. Never knew how to do that... but today i discovered font-lock-unfontify-region. Unfortunately, it's a function not command, so you cannot call it with “Alt+x”. So, i make one:

(defun unfontify-region (begin end)
  "Unfontify text selection.
See also: `font-lock-fontify-block', `font-lock-fontify-buffer'."
  (interactive "r")
  (font-lock-unfontify-region begin end)
  )

Added a code snippet on More Elisp Examples. The code shows you how to write a function that cycle thru states when called repeatedly, and also explains the concepts of lisp's “symbol property”, setting font in a frame.

On Dec 26 2009, 8:50 pm, Ccming wrote:

I very like the default style of PHP lanuage on Notepad++, hope I can use them on GNU Emacs.

Yes.

i don't recommend it because emacs's font style for programing lang keyword types are used across all langs. For example, function is blue, strings is a bit orange, coments are red, etc., for all langs. Also, emacs's font face coloring are designed so it's also usable when in 8-color terminal.

anyway, to do what you want, do Alt+x customize-group, then give “font-lock-faces”. There, you can use the mouse to select and change.

you can see a sample of how emacs coloring are for different languages here: Google-code-prettify Examples.

Am starting this emacs blog. Often, i have random tips or notes i want to write down. Too small to be part of tutorial, but still useful even to myself later. This blog also serve as news update for my emacs tutorial. I have a main blog Periodic Dosage of Xah Lee but that is not focused on emacs topic. Many people are interested in my emacs news but not others. So, this emacs blog will help.

What follows are emacs related stuff from my main blog in the past several months. I put them here to start with, and also gives some sense of the topics in this blog.

Ok, here's first blog entry.

when you use a hook, it is best to define it as a function, then add that to hook, instead of using a lambda. Let me explain.

Here's what a hook most people would do:

;; modify nxml-mode's shortcut keys
(add-hook 'nxml-mode-hook
 (lambda ()
 (define-key nxml-mode-map (kbd "<f8>") 'browse-url-of-buffer)
 (define-key nxml-mode-map (kbd "<tab>") 'html-next-content)
 (define-key nxml-mode-map (kbd "S-<tab>") 'html-previous-content)))

However, it is better done like this:

(defun xah-xml-mode-keys ()
  "Modify keymaps used by xml-mode."
  (interactive)
 (define-key nxml-mode-map (kbd "<f8>") 'browse-url-of-buffer)
 (define-key nxml-mode-map (kbd "<tab>") 'html-next-content)
 (define-key nxml-mode-map (kbd "S-<tab>") 'html-previous-content)
  )

(add-hook 'nxml-mode-hook 'xah-xml-mode-keys)

There are several advantage. One of them is that with a function name, you can now remove some of your hook stuff easily by calling “remove-hook”. Also, suppose you are using command-frequency-mode to know what commands you use the most. If you have lambda, the data will become unreadible with bunch of lambdas, instead of command names.

Of course, lambda in hook is so convenient, typically just used once in your emacs init file, and you don't need to manipulate it with remove-hook or others. But if you are using hooks in your elisp code in a package, it's best to define functions instead of using lambda in hooks.